Anxiety about phone

So to start off my S/O and I have been together for 3 almost 4 years now and have 2 girls. We have had issues with trust in the past because of inappropriate conversations he has had with girls on his phone. He has never physically cheated but he admits to emotionally cheating on me with a friend this last summer while I was pregnant with out second daughter. I want to have his phone password and he makes me feel crazy for wanting it. We were in therapy (not now with the stay at home order) working on our trust and communication after all this went down. To make me feel better I believe having his password would help. Not so I can be constantly going through his phone but just as a safety net for myself till I can feel more confident I guess. I am having a really heard time getting over everything that has happened in the last year and I think it is weird that I am not allowed to touch his phone... I can't even use it if mine is lost or anything. I feel like it isn't helping me rebuild that trust... Do any of you guys have any similar experiences or advice on the matter? Am I actually crazy for wanting his password? Thanks for reading my long post haha