Her parents are disagreeing and each of them is neglecting the rights of the other, and she is asking for advice
Question

My mother is not obeying my father as a wife should because my father is not responsible. He does not feed us normally, clothe us and does not give us good education and Islamic training. He also mistreats her, so she has taken up most of his duties as a man. But, I fear for my mother because the prophet (peace and blessings be upon him), said a woman's paradise is at her husbands feet. I also work and do my best to support my family. I really love and want them to have the best.
Praise be to Allah.Islam has ordained that each spouse should have duties towards the other. The husband has rights over his wife and she has rights over him, but his rights over her are greater than her rights over him, because Allah, may He be glorified and exalted, says (interpretation of the meaning):
“And they (women) have rights (over their husbands as regards living expenses, etc.) similar (to those of their husbands) over them (as regards obedience and respect, etc.) to what is reasonable, but men have a degree (of responsibility) over them”
[al-Baqarah 2:228]. 
Al-Jassas (may Allah have mercy on him) said: In this verse Allah, may He be exalted, tells us that each spouse has rights over the other, but the husband has some right over her that is exclusive to him and she does not have a corresponding right over him, because Allah, may He be exalted, says: “but men have a degree over them”.
End quote from Ahkam al-Quran by al-Jassas, 2/68 
Ibn al-‘Arabi said: Here Allah states that the husband is given superior marital rights over her.
End quote from Ahkam al-Quran by Ibn al-‘Arabi, 1/256 
One of the rights of the husband over the wife is that she is obliged to obey him, as Allah has put the man in charge of his wife with regard to instructing her, directing her and taking care of her, as a ruler would take care of his subjects, because of the physical and mental characteristics that Allah has given only to the man, and because of the financial obligations that He has ordained upon him. Allah, may He be exalted, says (interpretation of the meaning:
“Men are the protectors and maintainers of women, because Allah has made one of them to excel the other, and because they spend (to support them) from their means”
[an-Nisa 4:34]. 
Ibn Katheer said: … ‘Ali ibn Abi Talhah said, narrating from Ibn ‘Abbas: “Men are the protectors and maintainers of women” means they are in charge of them, i.e., she should obey him as Allah has commanded her; obedience to him means that she should treat his family kindly and guard his wealth. This is the view of Muqatil, as-Suddi and ad-Dahhak.
Tafseer Ibn Katheer, 1/492 
One of the rights of the wife over her husband is that he should spend on her, so long as she is obeying him and is not defiantly rebellious. The wisdom behind the obligation upon him of spending on her is that the woman is tied to the husband by virtue of the marriage contract, and she is not allowed to go out of the marital home to earn a living except with his permission. So he should spend on her sufficiently in return for intimacy and her being devoted to taking care of him. 
What is meant by spending is providing what the wife needs of food, clothing and accommodation. These things must be provided for her even if she is rich, because Allah, may He be exalted, says (interpretation of the meaning):
“but the father of the child shall bear the cost of the mother’s food and clothing on a reasonable basis”
[al-Baqarah 2:233]
“Let the rich man spend according to his means, and the man whose resources are restricted, let him spend according to what Allah has given him”
[at-Talaq 65:7]
“Lodge them (the divorced women) where you dwell, according to your means”
[al-Talaq 65:6].
And because the Prophet (blessings and peace of Allah be upon him) said: “Their rights over you are that you should provide for them and clothe them in a reasonable manner” Narrated by Muslim, 1218. 
Another of the rights of the wife over her husband is that he should treat her well and have a kind and gentle attitude towards her, because Allah, may He be exalted, says (interpretation of the meaning):
“And live with them honourably”
[an-Nisa 4:19]
“And they (women) have rights (over their husbands as regards living expenses, etc.) similar (to those of their husbands) over them (as regards obedience and respect, etc.) to what is reasonable”
[al-Baqarah 2:228]. 
In the Sunnah: it was narrated that Abu Hurayrah (may Allah be pleased with him) said: The Prophet (blessings and peace of Allah be upon him) said: “I instruct you to be kind to women” Narrated by al-Bukhari (3153) and Muslim (1468). 
We have previously discussed in detail, with evidence, the rights of each spouse over the other. Please see fatwa no. 10680. 
After this explanation, you will know that each of your parents has fallen short with regard to the rights of the other, and missed out on his or her own rights. The husband has failed to give his wife her rights of maintenance and kind treatment, and the wife has failed to be obedient and submit to her husband. 
What we advise you to do in this case is to advise both of them, wisely and gently. Explain to your mother the rights that her husband has over her, and what is enjoined by Islam of obedience and giving him his rights properly. She should not respond to his shortcomings with similar shortcomings, for whoever disobeys Allah concerning you, you should obey Allah concerning him. Allah, may He be exalted, says (interpretation of the meaning):
“The good deed and the evil deed cannot be equal. Repel (the evil) with one which is better (i.e. Allah ordered the faithful believers to be patient at the time of anger, and to excuse those who treat them badly), then verily! he, between whom and you there was enmity, (will become) as though he was a close friend.
But none is granted it (the above quality) except those who are patient, and none is granted it except the owner of the great portion (of the happiness in the Hereafter i.e. Paradise and in this world of a high moral character).
And if an evil whisper from Shaitan (Satan) tries to turn you away (O Muhammad) (from doing good, etc.), then seek refuge in Allah. Verily, He is the All-Hearer, the All-Knower”
[Fussilat 41:34-36]. 
At the same time, you should advise your father to fulfill the duties that his Lord has enjoined upon him towards his household and his wife, of maintenance, clothing and so on. 
If they respond, then all well and good; otherwise by doing that you will have done what is required of you of giving sincere advice, calling to that which is good, and enjoining what is good and forbidding what is evil. There will be no blame on you – in sha Allah – for their shortcomings. You should remember that what is obligatory for you is to honor your parents, treat them kindly, offer them sincere advice and try to reconcile between them. If one or both of them persists in what he or she is doing, their right to respect and kind treatment is not waived, no matter what extent their misconduct and errors reach. 
Someone asked ash-Shaykh Ibn ‘Uthaymeen (may Allah have mercy on him) about a dispute between his parents, and he replied: … With regard to the dispute between them, what you must do is two things: try to reconcile between them as much as you can, so that the dispute, enmity and resentment between them will be dispelled, because each spouse has duties towards the other which must be fulfilled, and part of honoring your parents is to try to dispel these disputes so that the atmosphere will be clear and life will be happy. 
The other thing is: it is obligatory for you to honor and show kindness to each of them. You can avoid making either of them angry if you conceal your kindness to one of them from the other. So honour your mother in some way that your father will not be aware of, and honour your father in some way that your mother will not be aware of. In this way you will be able to do what is required. You should not be content to let your parents remain in this state of conflict and dispute, or in a state of anger if you honour the other parent. What you must do is explain to each of them that honouring one does not mean cutting off ties with the other; rather each of them is entitled to a share of your honoring and kindness as Allah has enjoined.
End quote from Fatawa Islamiyyah, 4/196 
You should also offer a great deal of supplication for them in their absence, asking Allah to set their affairs straight and to help them avoid the tricks of the Shaytan. 
And Allah knows best.