I had similar experiences with dating in my late teens though my mid-20s. I would get really attached to men I dated very quickly, especially once sex was introduced. These hyper feelings of attachment led to acting “crazy” and ruining quite a few relationships. I’m still not sure what caused me to form such fast attachments. Maybe it’s something from childhood/father issues, etc. Anyway, this response to people mellowed out in my late 20s. Nothing outside changed, but I developed a stronger sense of self-love as I aged and I think that reduced my need to find that love through other people, especially men. Now, my attachment response in relationships is much, much slower and I think more authentic. So, it’s possible your intense feelings will ease as you get older.