As-salamu alaykum brother,

Shokran for writing to our lives session with your most important concerns and issues. I can understand why you are upset and distraught. You are denied the chance to marry one whom you would like to due to a parental miscommunication. We are to love, be kind to and respect our parent and it is a sin to treat them poorly or with disrespect. However, as adults we are free to chose whom we will marry as long as that person is within Islamic guidelines for a marriage partner. It appears you both are, thus it is a shame that your parents have “forbidden” the marriage and threatened to cut you off, which is a sin as well. In fact it was reported that (1)

“ A’isha reported that the Prophet, may Allah bless him and grant him peace, said, “Kinship (rahim) is derived from Allah. If anyone maintains ties of kinship Allah maintains ties with him. If anyone cuts them off, Allah cuts him off.” Therefore, your parents threats to cut you off as well as their grandchildren is a very serious offense.

Sadly, there are many proposals that could have produced happy, long marriages if it were not for parental interference. As your “fiance” accepted your proposal and does in fact want to marry you, there is no reason for you both not to marry. As we see from the following hadith it is her decision. (2)

“A previously married woman has more right to decide about herself (with regard to marriage) than her guardian, and a virgin should be asked for permission with regard to marriage, and her permission is her silence.”

It further states “Seek the permission of women with regard to marriage.” It was said: “What if a virgin is too shy and remains silent?” He said: “That is her permission.” (3).

While we desire to listen to our parents out of respect, love and Islamic law, there are obligations parents have to children as well. One includes not preventing a lawful marriage as we are commanded to marry. While they may feel they are right in their denial and you may feel that you must obey their command regarding this, it is not true. You are grown. Their denial appears to be based on cultural norms from your region as well as mis-communications between the families.
I would kindly suggest brother, that if you and the girl desire to marry that you do so. I would respectfully and kindly sit with your parents and inform them of your decision. Use the Qur’an to illustrate how we are to chose our mates. Please do also point out the ayats wherein Allah forbids us to cut off family. Insha’Allah point out that while you love and respect them very much and will always care for them, you have decided to marry this girl. Additionally as there was a mis-communication between the families, I would offer to set up a meeting to sort out the problem.

I suspect there will be anger, hurt and upset feelings regarding your decision however this is to be expected. Make duaa to Allah to soften their hearts and insha’Allah over time they will get over their anger and begin to accept what it is that they had no power over. In fact, it might not even be about you and the girl but more about power and ego-which is haram. While it may be hard on your marriage for awhile, insha’Allah your parents will accept the marriage once their anger has subsided. What would be truly tragic, is if you married another, still thinking about the one you really wanted to marry -and lived an unhappy life. It would be unfair to the girl as well whom your parents have chosen for you.

So please brother, do make istakharra, ensure this is the girl whom is right for you and if so marry her. Your parents will get over their anger insha’Allah in time. There is no sense in losing a pious life partner over cultural norms and power struggles between families.
1-https://sunnah.com/adab/2/9
2-https://sunnah.com/search/?q=permission+for+marriage
3-https://sunnah.com/nasai/26/71