My relationship is going bad

I just feel so broken and I don’t feel like the person I once was. This person is passive aggressive and makes me feel crazy. But he does nice things for me and acts so sweet and loyal but he’s been caught lying many times and I just don’t know anymore. We have a kid together and he’s trying to prove to me he’s loyal but it’s like he gets soft each time we have sex!!! He has had a p*rn addiction and I told him how it made me feel & asked if he’d be ok with me looking at dick fucking myself he said he wouldn’t be ok with that at all. He hasn’t watched it in months he says but I’ve caught him masterbating in bed when our toddler was asleep on bed. I don’t care if he touches himself when he’s alone just no p*rn . But idk I noticed this past week he’s been going soft inside me and I just feel so bad he said idk why it’s happening and I said bc you jerk off too much. And he’s like no I haven’t. But he’s a big liar and was caught on private browser like 2 years ago. He does receive spam emails of girls wanting to meet up and I’m just wondering if those are from girls he’s talked with? Or if he was on cam sites. I’m so upset hurt and I just don’t know anymore it’s been a few years trying to work past his lies. He said he’s changed and wants his family but idk I can’t trust him.