I too am a guy.
Had this severe problem of no orgasm during sex. I've been masturbating since about 14 years. Guess what, the bad news is that porn + masturbation will GREATLY hurt your sex life with a real human being. The good news is that there is a simple fix. Simple in theory, but complicated in practice, it all depends on how much perseverance you have.
When I first had sex with a girl i found super attractive, i didn't climax, and our first time was just weird and created more tension in the relationship. That destroyed that relationship in the end. Then I met this other girl, also very attractive. Same thing, many night we'd try but after over an hour of going at it, nothing. The only way I could even come close to finishing is by thinking about pornography or by masturbating. Luckily this one was more understanding and it didn't scare her off. Then I searched many internet chat forums, and the consensus was: you have to stop masturbating with your hand, as your body is used to your hand, it being much tighter than a woman's vagina. So I did, and I used a light grip. That helped a little, as I got more sensation during sex, but I still needed to think about porn, the good news is that I was able to climax. Then I realized perhaps porn on its own was the culprit, so I cut that out. However I kept masturbating and thinking about it, and things quickly got back to where they were, no orgasm, and long sex session. In the end, I gave up both porn and masturbation. One of the hardest things you'll ever do. And now I can orgasm in ~ 10 minutes, and I feel absolutely everything. There is this thing called neural plasticity, and you've taught your brain only to come from porn + masturbation. Porn has unrealistic looking women, doing things most women wouldn't agree to. Trust me when I say this: give up porn + masturbation cold turkey for 2 weeks, and you'll see instant results. If you can't give it up that fast, fine, take your time, but use it less and less and don't let yourself slip otherwise you'll just ruin things. The bottom line is, you have to desensitize your brain to real women. Your issues might be rooted deeper than this, but I'm telling you, it will work!
Good luck m8 and all the best Smile