Beware of the Whispers of the Shaytan about Allah
Question

For two weeks this question has been haunting me and I cannot find an answer to it, but in sha Allah you will have the answer:
What is the evidence that Allah does not lie, or what is the evidence that He always tells the truth, and why will He never lie?
I know that this is a strange question, and I felt too embarrassed to ask anyone about it for a while, but I looked for an answer and I feel a kind of anxiety even when praying.
Praise be to Allah.By Allah, we do not know which of your two issues we find stranger, that you have gone along with the whispers of the shaytan (devil) to such an extent that brought you to the brink of the abyss and nearly made you fall in, or that you find this question difficult and are not able to find an answer to it.  
What do you know of your religion, if you do not know this? 
What do you think of your Lord, if you are asking about this? 
When her freed slave asked her: O my mother, did Muhammad (peace and blessings of Allah be upon him) see his Lord? ‘Aishah, the Mother of the Believers, (may Allah be pleased with her) said: My hair stood on end at what you said.  
If the hair of the Mother of the Believers stood on end because of alarm for the one who asked her this question: Did Muhammad (peace and blessings of Allah be upon him) see his Lord, i.e., in this world – although the believers will see Him in Paradise and that will be the greatest of their joys (may Allah not deprive us of it) – then how should one react to your question? 
Have you left your heart empty to such an extent that the shaytan can toy with it and cause it to end up like this? 
Have you heard of the report narrated by Muslim in his Saheeh from Jabir who said: A man came to the Prophet (peace and blessings of Allah be upon him) and said: O Messenger of Allah, I saw in a dream as if my head was cut off. The Prophet (peace and blessings of Allah be upon him) smiled and said: If the shaytaan toys with one of you in his sleep, he should not tell the people about it.” 
If a dream such as this is regarded as the shaytan toying with a person, then what would the Prophet’s (peace and blessings of Allah be upon him) response be to one who saw what you have seen in a dream? What would he say if the shaytan toyed with him when he was awake, and not in a dream? 
It is natural that you should feel ashamed and you should weep for yourself if the shaytan has gained so much power over you.  
Yes, we understand that the shaytan may toy with a person in such ways, but he should not go along with the ideas instilled by the shaytan and try to discuss it and look for evidence for it. Rather his deeply rooted faith should protect him, for the shaytan is evil and his plot is weak:
“… ever feeble indeed is the plot of shaytan (Satan).” [4:76]. 
It was narrated that Abu Hurayrah (may Allah be pleased with him) said: The Messenger of Allah (peace and blessings of Allah be upon him) said: “The shaytan comes to some of you and says, ‘Who created such and such? Who created such and such?’ – until he says, ‘Who created your Lord?’ If that happens, then let him seek refuge with Allah and stop thinking about that.” 
What do you think the Prophet’s (peace and blessings of Allah be upon him) answer would be to this “difficult” question posed by the accursed enemy? 
One should seek refuge with Allah from this waswas (insinuating whisper), and stop thinking about it or getting carried away with it, because the accursed one does not need an answer to this question. He knows that his question is pure fallacy, for it is not befitting that the Creator should have a creator, otherwise He would be another created being.  
Rather his aim is to stir up doubts until he gains control over one who dies in such a state, if he can. Al-Hafiz Ibn Hajar (may Allah have mercy on him) said in his commentary on the hadeeth (report) quoted above: 
“‘Who created your Lord?’ If that happens, then let him seek refuge with Allah and stop thinking about that” i.e., let him stop getting carried away with that, and turn to Allah in warding it off; he should realize that he (shaytan) wants to corrupt his religious commitment and his reasoning with these whispers, so he should strive to ward them off by thinking of something else. 
Al-Khattabi said: The point of this hadeeth is that if the shaytan whispers such thoughts, one should seek refuge with Allah from him and stop debating with the shaytan about it, then this waswas will diminish. There is no end to the shaytan’s whispers, rather every time proof is produced to silence him, he moves on to something else until he finally makes one confused. We seek refuge with Allah from that. … But his saying ‘Who created your Lord?” is contradictory and is a flawed argument, because it is impossible for the Creator to be created. 
Al-Teebi said: Rather he enjoined seeking refuge with Allah and distracting oneself with something else; he did not tell us to ponder and look for evidence, because the knowledge that Allah does not need a creator is a basic fact that is not open to debate, and because getting carried away in thinking about that will only make a person more confused. If a person is in such a state, he has no option except to turn to Allah and seek His protection. 
The hadeeth also implies criticism of asking too much about that which does not concern one and that which one has no need to ask about. It is also one of the signs of Prophethood, namely his foretelling something that was going to happen and then it happened. End quote. 
As the Prophet (peace and blessings of Allah be upon him) enjoined putting an end to such whispers and not indulging in them, then the believer, if he is overwhelmed by any such thing, and if the accursed enemy instills such a thing in his heart, then he will regard this waswas as something serious that has befallen him. 
It was narrated that Abu Hurayrah (may Allah be pleased with him) said: Some of the companions of the Prophet (peace and blessings of Allah be upon him) came and asked him: We find in ourselves something that is too awful for any of us to speak of it. He said: “Do you really find that?” They said: Yes. He said: “That is clear faith.” [ Muslim]
Al-Nawawi (may Allah have mercy on him) said: What this means is: The fact that you think of this waswas as something terrible is a clear sign of faith, for if you dare not utter it and you are so afraid of it and of speaking of it, let alone believing it, this is the sign of one who has achieved perfect faith and who is free of doubt 
O slave of Allah, the man of dignity who has some standing among people would refrain from lying and would hate lies to be attributed to him. The story of Abu Sufyan with Heraclius concerning this matter is well known, so how about if this noble and dignified man is a believer? For lying is incompatible with faith.  
How about if one imagines the Messenger of Allah (peace and blessings of Allah be upon him) telling lies when he is the truthful one? This is an idea that would make the skin crawl and the hair stand on end.  
It seems most likely that there are two reasons why the shaytan has gained control over you: 
1-    You have turned away from focusing on remembrance (dhikr) of the Most Merciful, studying His verses and what it says in His Book of His most beautiful names and sublime attributes, and acknowledging His greatness, majesty, beauty and perfection that are mentioned in His Book and in the sunnah (teachings) of His Prophet (peace and blessings of Allah be upon him). 
2-    Perhaps it is a punishment from Allah because of the first reason, which is your keeping company with the devils among men, who have been supported by the devils among the jinn and helped by them against you.  
Those companions were not necessarily friends of yours who come and go with you, rather that may have been via the internet as idle curiosity may have led you to go to some atheist and anti-religion chat rooms, where one of them stated his specious argument and it settled in your heart and led to the problem that you are now suffering. Allah says (interpretation of the meaning): 
“And whosoever turns away blindly from the remembrance of the Most Gracious (Allah) (i.e. this Quran and worship of Allah), We appoint for him shaytan (Satan ‑ devil) to be a Qareen (a companion) to him.
And verily, they (Satans / devils) hinder them from the path (of Allah), but they think that they are guided aright!
Till, when (such a one) comes to Us, he says [to his Qareen (Satan/devil companion)] ‘Would that between me and you were the distance of the two easts (or the east and west) a worst (type of) companion (indeed)!
It will profit you not this Day (O you who turn away from Allah’s remembrance and His worship) as you did wrong, (and) that you will be sharers (you and your Qareen) in the punishment.” [43:36]
Set your heart straight and turn to your Lord, and acknowledge Him as He has told you in His Book. Turn to His Book and read it and ponder it, and keep your tongue busy with remembrance of Him (dhikr), for that will protect you: 
“I command you to remember Allah, for the likeness of that is that of a man whose enemy comes after him, until he comes to a strong fortress where he protects himself from him. Similarly, a person cannot protect himself against the shaytan except by remembering Allah.”  [Tirmidhi and classed as saheeh/authentic by al-Albani.] 
And Allah knows best.