When you told your cousin, SIL, and grandmother your # of sexual partners, what was your goal? Were you seeking approval from them?

I don't think the primary issue here is whether or not your family believes you but why you are sharing such intimate details with them and why at age 30 you need their approval of your sexual choices? It's really not their business. They may or may not approve. The more people you share delicate info with, the more you unwittingly open yourself up to judgment or condemnation.

That's why most adults will keep their private sexual history to themselves. Most won't even share such details with their spouse. They may possibly share with one trusted friend or therapist if they wish to discuss.

It may seem like I'm not answering your questions but I think you are sort of looking at this from the wrong angle. You could spend the rest of your days trying to figure out if your family believes you or not....but wouldn't that be a waste of your life? We cannot truly know what is going on in someone else's mind....family or not. Someone could say I believe you and be lying. Someone else could say i don't believe her but they really do and don't want to say so. People are going to think whatever they want so we need to limit what we share with them.

Perhaps you are enmeshed with your family? Does that resonate? You (or they) don't perceive yourself as a separate entity from them in your own right?

Your sexual choices are not their choices so their opinion really doesn't matter. Can you see that or does that sound odd?

it is nice to have people around who like and appreciate me but ultimately the only approval I actually need for the rest of my life is my own. I need to be okay with my own choices. Other people will figure out theirs.