He took an oath 8 years ago that he would marry her
11-1-2011 | IslamWeb
Question:
What if i had taken oath that I swear by Allah that I have given myself to a man to marry me and he also taken oath that he swears by Allah he will get married to me. Does it amount to any kind of obligatin on the man to marry me? I will be his second wife. He is promising me since last 8 years and finally he denied due to social constraint. Please advise ASAP
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad 
is His slave and Messenger.
First of all, it should be noted that this man is not obliged to marry you just because he had made an oath to this effect. So, if he marries you, he would have fulfilled his oath, and if he does not marry you, then he has broken his oath and in this case, he is obligated to expiate for breaking his oath. Breaking one’s oath may be better sometimes than fulfilling it; it is confirmed in a Hadeeth that “Whoever makes an oath and sees something else better than it, then he should do what is better and expiate for breaking his oath.”
Ash-Shaafi’i 
said in his book "Al-‘Umm" : “If someone makes an oath to do an act of righteousness, then we would order him to fulfill it and not break it, like saying: “I swear by Allaah that I will fast today” or “I swear by Allaah that I will perform such and such supererogatory prayers.”, so, in this case, we would say to him: 'Fulfill your oath and obey your Lord, and if he does not do so, he would have broken his oath and he should expiate for breaking it.'”
Therefore, our advice to you is that if this man turns away from marrying you, then you should ignore him as well, because it might be that there is no good in him marrying you, and being a second wife may be a cause of many problems. Indeed, there are so many other men, so you should ask Allaah to bless you with someone better than him, and you may seek the help of your relatives or female friends to look for a husband for you.
For more benefit, please refer to Fataawa 82471 and 81356.
Allaah Knows best.