Bf advice

I am a jealous person. I've got played in my past and I'm scared of getting played by my current boyfriend of 3 years. He doesn't understand that it hurts my feelings when he messages girls on any form of social media then deletes it. I find it shady and I feel like it's a form of cheating. I've seen some things like messages when he leaves his accounts logged in and later if I confront him about it he'll just try to pin it on me like if I did something wrong. He would try to make me feel bad and tell me he'll leave me if I don't stop being so jealous. What should I do ?