1- The promise was regarding a head covering. (instead of a wig I said I’ll wear a tichel)
2- What’s bothering me is that because I was so terrified about this phobia I promised that if will be zoche to get married and have kids I will put it on. Now I’m worried that because I promised it depending on these two conditions, that it will chas veshalom negatively affect me. so my question is if I need to take on a different thing that I can do instead of the promise that im being matir neder and if my Rav has to know these details??
3- And again, halachically is it ok if I just tell the Rav that I had a strong phobia about something? Or do I have to tell him the details of it?
You can be matir it, and instead of wearing a tichel, it can be that you will wear a tzniusdik sheital that the Rabbonim agree to. This way you will have the kabola that you made and after you will be matir neder (if the Rov permits it) you won’t have the stigma of the neder anymore. You only have to tell the Rov that you have a strong phobia regarding Yom Kippur. You don’t have to tell him that it was because of the difficult teenage years that you had, but only that you have a strong fear regarding Yom Kippur.