"The whole point is that the person you stop trusting is mostly yourself"
This...... A million times over.
If something feels off, and your gut instinct is telling you so then usually something is off.
I caught a cheating ex once and it saved me from getting married to him, he'd been getting ridiculously close to a woman at work (an intern)... Had mentionitis, took her to an Oasis gig when I'd have wanted to go, staying at the office late, going out after work a lot etc.
When I confronted him about it and also asked his work mates what the hell was going on, they said they all wanted to tell me but they didn't know how.
He completely turned it round on me, gaslighting the lot. His final words to me when I moved out of our house was "you've ruined my life"..... Erm ok then.
It depends whether you want to carry on living your life with someone treating you the way they are and feeling uneasy. I'd agree with what others have said, it's a sign things are very wrong in your relationship if you feel the need to do this. But if it turns up something then it might save you from wasting years of your life on someone who doesn't deserve it.