I have a fear of my boyfriend masturbating

Hi TSR, please knock some sense into me.

We're both 19, gay males, students. We've been together for over half a year and this hasn't been an issue until now. We're incredibly loving, always do nice things but this one issue I cannot for the past week get out of my head.

So, my laptop died and I had uni work to do so he let me use his laptop. He uses chrome for porn which I didn't realise and clicked on to see that every suggested website was porn. I decided to see what type of stuff he watched so looked into his browsing history and what upset me the most was the times he watched them. He watched it once 4 hours before I was coming over to see him, and on two occasions (from what I saw) he watched it in the day time. I decided to look at the texts on my phone because we always text and I'd wondered how he had time to do this. What I saw was that he wouldn't be replying to me for like half hour-hour, I would be texting him and calling him on one instance because we were arranging plans for the day and he just went quiet. On both occasions he made an excuse that his phone was playing up (my calls wasn't going through and he's told me now he put his phone on airplane mode) and the second time he said he was making food. It really upsets me that he wouldn't have the respect to do it when we weren't speaking, but just blocked me out to masturbate over other guys (usually solo videos).

It bothered me a little before, but now it bothers me to insane levels. When I'm not with him I'm scared he's doing it to other people. I went to sleep last night and he wasn't tired because his body clock is messed up and even now I'm worried he did it last night.

I've spoken to him and he assures me that he loves me, that he won't shut me out to do it again and won't do it before I come over but I'm still overly paranoid about this one stupid issue. Can anyone relate? I think the fact he shut me out to do it has turned the issue in my head much bigger where I'm now jealous he even does it.

I won't lie, sometimes I masturbate but I know it's nowhere near the amount that he does, we could have sex four or five times a week and the days I don't see him he still does it once or twice a day. Even if he knew I was coming over in the morning he would do it in the night. I on the other hand went from masturbating like three times a day to barely ever doing it, so it literally makes me feel like ****.

I know my thoughts are illogical but I can't get them out of my mind!