Help :( Relationship issues! Please help?!?

[john]

I KNOW ITS LONG BUT PLEASE READ. I"M READY TO DIE Please help.

I'm in a relationship, and we've been together for awhile. And we're pretty serious. And we've had some issues in the past and we've worked out issues. Everything was going good.
One of my biggest concerns, me being a virgin, is her sexual past. I basically hardcore forced her to tell me everything about her sex life the day after i asked her out.
And i believed her. She said things that made sense. She said she told me everything.

Now before i get to my main point, note that i have trust issues. Extreme trust issues. So bad. I've been in FORTY relationships and each ended in a lie, no matter what. So my trust is just gone.

Now here is where the problem rises.
So me being the overconcerned boyfriend i am, i found a post way way back on a social media website. Like forever ago. And it was a question asking "Have you ever had a one night stand?" And the response was "Yes."
So tell me... if she told me everything, what does this mean?
Well i actually called her and confronted her. And we got into a fight. She told me she did NOT have a one night stand. It was her friend on her account.
Well there are tons of evidence against her. A few being, Why didn't she delete it? Why didn't she notice or remember it until now? And if it was her friend, why would her friend do that? Those are the few of the MANY i brought up to her attention.

She claimed she didn't know how to delete it. (She really isn't that smart, so its believable.)
She claimed she didn't like talking about her past to me it made her seem inferior so she never brought it up.
She claimed she's not friends with that girl anymore because of it.

Also, she barely trusts her phone with anyone, even me. So how did her friend get ahold of it?

Please HELP ME. I want to believe her. But from past experience, and my mindset will NOT allow me to believe her.
I'm not asking you guys if she's lying or not. I'm asking you what i should do.
She's my girlfriend, should i just **** it all and take her word for it?
If so, how do i get this trust issue out of my head? I will remember it FOREVER. Every kiss i get, i'll think of it. Every hug. Everything she says i don't believe now, just because of this.
I'm damaged and i need some help. Please help me. Please.

[susanperr]

Trust needs to be earned and built upon. If you don't trust her you should have an honest conversation with her and tell her. How she acts and responds after that should tell you alot. If you don't trust her, you just can't and nothing there will change. You could give her another chance. But, you are carrying baggage into this relationship from the past and that may not be fair to her. Try not to compare her and try to be open-minded. Otherwise, forget it and move on. Trust your instincts.