I am still a young guy in college. On many occasions with different girls, I have had problems with getting/maintaining an erection during sex.

With a girl I've currently been hooking up with, it's been 6 or 7 times now where we've tried, but I've only been able to get and maintain an erection during sex one of the times (and it was great sex)

I'm almost positive this is an issue with my brain and not my dick. I always get hard from making out, cuddling, and foreplay but it's only right at the moment I'm about to put it in, that I go limp. Then after that no matter what I try to do I can't get it up until she starts blowing me again.

It's been ending with her giving me a blowjob which i can always stay hard from but if she stops for a second and we try to fuck again, it goes down within a matter of seconds.

I've learned about how porn / masturbation can lead to ED on r/nofap and r/pornfree. So I haven't watched porn in over two months and I've been masturbating much less.

I also know that overthinking the fact that I'm about to lose it will only make me more likely to go limp too.

Anyway I'm just looking for advice on how to maintain frame here while I psychologically deal with this issue.

The girl has been really good about it. She has not once acted disappointed or tried to pressure me into getting hard enough to fuck her, but the last time it happened, she could tell I was frustrated, which shows weakness and vulnerability.

So, what's a good way I can handle this while still seeming in control and in my own frame?

And any tips from people who have had a similar problem with ED and overcome it would be great too.

Edit: I am physically healthy and exercise regularly. I drink and smoke moderately but (this happens when I am sober as well)