They called upon the angels to witness their marriage
Question

                I am a female student living on my ownaway from my family.... i became friendz with one of my colleges last yr .he was ill those days and even had some more problemsin whichhe definitelyneededsomeoneto rely on and few words of strenght.i became thatsupport for him that time.I thought it is nice to help people.....Alllah would reward me for that .But after amonthor sdo we became very good friendzand later got much involved in each other.till now we never touched each other..... once we were playing,i dont remember what happened that day ....he leaned on me and kissed me .both of us being muslims felt guityand at our own placdfes asked forgiveness from allah ...and i dont remember how the same thing happened once moreand we decided to marry...As we were students and due to some economical and social problems we were not able to do it properly and disclose it .....Moreover we nthought its allah who knows everything and we should be clear infront of him. one night after offering salat of isha and two rakaa' of nafilahwe started searching for verses and rules and regulations of marriage in quran.We found some lines but not exact what we wanted that time ....Any how we read few verses from it and sweared holding quran in our hands that we consider each other as our spouse.and would never betray each other ...and thought Angels wouild be our witnesses. and therefore we thought we are married..and kissing and holding each other never haunted us...and we never felt guilt... after 3 months or so ,as we thought we are married many times we shared bed. This yr (after11/12 months),i was reading some questions on this site on divorce and marriage ...(i used this site earlier but never used it for this topic as i never thought i did wrong ...)and there i foundcertain questionslike this but not exactly...there arouse a doubt in my mind that i am practicing wrong thingsso i spoke to him and we stopped practicing it .... sir,we want to know ,whether this marriage is considered or not ...? have we done "zinna"and whether we will be punished for it even if we repent... And sir,if we want to marry in futurecan we marry(if our marriage is not considered)? .
Praise be to Allah.What 
    happened between that man and that woman – based on what is mentioned in the 
    question – is undoubtedly zina. Where was the woman’s wali (guardian) in 
    this marriage? It is strange that the angels were witnesses to this marriage 
    but they did not see those witnesses. 
What you 
    have to do is repent to Allaah from what you have done, and realize that you 
    have committed a major sin. The Prophet  (peace and blessings of Allaah 
    be upon him) said: “No adulterer is a believer at the time when he is 
    committing adultery.” Narrated by al-Bukhaari (2343) and Muslim (57). For 
    more information please see question no. 
    11195 and 
    21223. 
If a person 
    repents, Allaah rejoices at his repentance and accepts it and forgives him, 
    as Allaah says (interpretation of the meaning): 
“And 
    those who invoke not any other ilaah (god) along with Allaah, nor kill such 
    person as Allaah has forbidden, except for just cause, nor commit illegal 
    sexual intercourse  
    and whoever does this shall receive the punishment.
69. The 
    torment will be doubled to him on the Day of Resurrection, and he will abide 
    therein in disgrace;

    70. Except those who repent and believe (in Islamic Monotheism), and do 
    righteous deeds; for those, Allaah will change their sins into good deeds, 
    and Allaah is Oft‑Forgiving, Most Merciful”

    [al-Furqaan 25:68-70]
See also 
    questions no. 27113, 
    624 and 
    20949. 
They have to 
    cut off all ties with one another, so as to close the door to temptation and 
    desire. If they want to have a good, legitimate relationship, then they 
    should enter houses by the proper doors, as Allaah has prescribed, and they 
    have to fear Allaah and be patient in heeding His sacred limits. A person 
    may be able to put up with the pain of separation but he will not be able to 
    put up with the heat of the Fire. So let them keep away from one another, so 
    that they will not fall into doing that which will earn the wrath and 
    punishment of Allaah, or let them hasten to get married in the proper 
    Islamic manner, after repenting from what they have fallen into of zina. And 
    Allaah knows best.