Most Helpful Guy
Where's the love? Your marriage will fail unless something drastic changes. It already sounds pretty miserable. You don't trust him (maybe with good reason) and he doesn't respect you. in my opinion you would be better off without him, then maybe you could find someone who can give you love.
Most Helpful Girl
Why are you signing into his instagram and deleting people?
First of all, if he's breaching your trust you either work it out or you end it. You monitoring all of his activity isn't going to fix anything - you need to fix the problem.
Work out your deal breakers; and be realistic. Him liking a half naked chicks pic I sn't going to end your marriage; him chatting up your neighbour and asking for nudes is. Talk about your boundaries and why you feel that way without being accusatory - use "I" statements.
Explain your repercussions, "if you still feel the need to chat up women and I find out, you need to move out of the house" and stick with it.
Stop going through his things. You set your boundaries; give him the opportunity to step up to the plate without being monitored like a child.
My husband and I have passwords, but each other's fingerprints are keyed in if we need to use their phone. I would NEVER go through his things; if I was suspicious I would ask him directly and get him to show me if necessary. He respects my privacy too
We had the same kind of issues you are when we first started dating but sorted it out with the above: I made my boundaries perfectly clear and gave reasons for why I felt that way and when he broke them I kicked him out. He sorted himself out before even trying to come back and proved himself worth