I am not trusted in my relationship. My partner insists that I am but behavior just shows time and again that I am not. We’ve been together almost ten years, I’ve never been unfaithful. A year and change ago, an ex friended me on facebook. For a while, the only interactions were just normal liking or commenting on various facebook crap. Never anything more than any other facebook friend. Then my grandfather died. Like a normal person, she offered condolences and we had a conversation because she knew him. This set my partner off and in the weeks after I was told to get rid of her altogether. I did. We are no longer facebook friends and I have had no contact with this person whatsoever. My partner constantly stalks her thru her facebook. She constantly checks my phone and emails and facebook for any signs of cheating, presumably with this person but could be anyone. I don’t hide or delete anything so this isn’t an issue but the lack of trust is. I’m told that if I’m not doing anything wrong then I shouldn’t have anything to hide. What bothers me is that we’re now like 9 months later and she’s still checking my stuff and still stalking my ex. Still hasn’t found anything, but it really hurts and every time I bring it up it’s a huge fight. There’s also a double standard because she’s quite good friends with her ex and other exes and I really don’t stop her from being friends with anybody. But anytime she suspects something of me all of my stuff gets rifled thru and I walk around on eggshells so that I don’t say anything about it.
In short, how do I stop caring about this?

[Just because you two have a history of being together does not mean you need to stay together. Maybe the relationship has run it’s course. You don’t speak of any other problems, so I don’t know whether that’s the case.
I think you two should maybe look into counseling with a neutral third party.
I’m not saying this is the case here but often times when one partner cheats, they will become paranoid that the other person is doing so.
[I don’t think you can stop caring about this, and nor should you.
If a relationship is ever going to work, there has to be trust. So I’d say the solution here is to figure out how to get your partner to trust you, not how to get yourself to ignore your partner’s trust issues. And for that to occur, the two of you will have to sit down and openly discuss why she is so unable to trust you.