husband masterbates nearly every day, is this normal.

we spend a lot of time together actually. In face we hardly do anything without each other. We date about once a week. So I thought everything was wonderful. Everyone always called us the wonder couple because we do everything together and never fight. So then I find these texts and I was really upset. they were deleted but I downloaded a program to bring them back. I read them. there wasn't much there but he did meet with her a couple of times and lied to me about it. I know nothing happened between them but he at least entertained the thought. He asked her if she was interested in him and she said she wouldn't so long as he was with me. He told me later that he only asked that so he knew if he had to distance himself from her. I don't believe him about that but he didn't leave and he didn't do anything with her. He has low self esteem and he has only had one partner other than me so I think he likes the feeling of someone else being interested in him, which I know we all do but I also know he crossed the line. He says he won't admit till the day he dies that she was anything because she wasn't. Anyway we have mostly move past that but I brought it up because it was a recent event. I asked him to go to counselling but he won't, he says he hates to talk. Talking about things just makes them worse. I am going to counselling myself because I have confidence issues, and to help me deal with this, and I was cheated on in the past so I have trust issues. He knows I have trust issues and he said he feels like I check up on him and gps track him all the time. Which I don't and if I did I would have confronted him about her way before I did.... anyway we have been working though that and I'm mostly recovered. (He left for about 2 mins when I first confronted him - he ran away- and then I brought it up again and asked him to leave and he said no he wouldn't ruin our marriage if I wanted to end it I would have to leave) oh and we have twin 6 year olds. So from then till now he has been much more cuddly and affectionate. He tells me he loves me constantly. Then I catch him masturbating and since then I have been looking at the internet usage so i know he does it in the shower on average every other, and sometimes at night. He using porn (not that I care about that so much) but I don't know why he would masturbate if he knows I would help him out anytime. I have told him this and I am always willing to have sex. he said it is a personal private thing and it has nothing to do with me or sex with me or him not being attracted to me or bored with me in anyway. He wasn't happy about it but he did talk to me a bit. But he said he was mortified and embarrassed about it. My biggest issue is that he has left bed with me where I just finished giving him a massage and offered to do other things to go run to the bathroom get in the shower and jerk off? what the heck? I can't help but feel rejected and that if he masturbated less we'd have sex more. Though like I said our sex is great and it is pretty frequent but most peoples' standards (multiple times a week generally) but I would happily have it everyday. I should also mention that he says I am insatiable and that he can't seem to satisfy me and that he sometimes feels pressured to have sex. I am trying to fit in anything that I think is relevant. Sorry for all this but i really want some thoughts and opinions.