OP,
I really feel for you. Its not an easy situation.
My husband is the same. At the beginning I dont think it really registered as an issue. We have been together 20 years now. We didnt even have sex on our wedding night. He always has to finish himself and i must have hated it then i just didnt acknowledge it like i do now.
We had to have IVF as it turned out he also had a fertility issue.
We saw a sex counsellor a few years ago and my husband was very adamant he doesnt have a problem. He says there are other ways to have sex and his way is normal. He has only ever had sex with me. Ive had a few more partners and its not normal. But he wont address it. He tells me its not me etc but i feel im not sexy enough as he can finish himself. Maybe 1 month every 5 years he can finish normally. No idea whats different about those times.
We've got past the child making now which took 10 years due to IVF. Now sex should be fun and it isn't so we have stopped having it. I think he has gone off it as well. I've told him so much over the years that him not ejaculating bothers me and he basically ignored me but when we saw the counsellor 2 years ago it bought it home to me that he really doesn't accept its an issue. So ive been more forceful about it being an issue and thats soured our whole relationship. Im not cruel though. He would want more sex than me and id tell him i dont want him to wank and he would always blame me for not wanting sex instead of realising i dont want to watch him wank over me again. I kept quiet for 19 years but eventually would say just go have a wank yourself. He would say its not the same, i want you etc etc. But it feels like we do stuff to each other not together. I want a quickie. Id love to be able to have sex somewhere other than the bedroom but we cant as it takes too long and always ends up with him wanking. Id like some passion.
I never understand how he could still want sex knowing that i hate the ending. He seems to be oblivious all this time. If i was doing something during sex that upset him it would have put me off years ago. I also cried after sex sometimes when i was ovulating as he couldnt make me pregnant and i wanted a baby. Even that never put him off.
We have talked about divorce but we have 2 kids, large bills and there are other things to consider.
If i was in your position i would leave now. I know its not that easy but living in a sexless marriage wont get easier either. I know some people do it but i cant. Im also annoyed as it shows he blanks out stuff he doesn't agree with. Because he thinks his normal is acceptable so he blanks out the rest. That outlook has shown itself in other areas in the 20 years so its not a trait limited to sex, but obviously i didnt know that early in our relationship. If we seriously disagree on something he just shuts down and ignores it. So when we found out he had a fertility issue he used the same approach. He cant have kids so we cant have kids. end of. he thought that was fine and ignored anything to the contrary. I did get my kids in the end but he made it much harder than it needed to be. Other things are the same though. If he doesn't agree he never backs me up or supports me.
He sounds terrible writing this. He has good qualities too. Sorry its long winded. Im just trying to say its probably an indicator of how he will tackle other challenges in life too in that he will refuse to be drawn in as he thinks its fine.
I dont think i could have been brave enough to leave all those years ago due to a sex issue. But in hindsight with the other issues I wish i had. Then i could have had a family with someone else in a much more normal way. In a way i have just put off splitting up 15 years and now its complicated by 2 kids and joint finances.
Good luck.