Open dialogue prefacing your interest prior and explaining you’re working through it is healthy. They saved you a lot of heart ache by making it about them. Emotional maturity is key for both sides. It never hurts to continue your work regardless of dating. Go with your gut!
Condoms are EVIL.
Necessary, but I’ve never been able to come in a condom.
If I wanted to fuck a piece of rubber…
Agree with outrageous moon owl, however that’s not helpful after the fact.
I’d go back to basics - SPP - lock in the affirmations, take the time to do the pelvic floor and kegel exercises each day. Build your confidence little by little, and when you are next in that sexual situation let your partner know that it’s normal for you to get hard and soft during sex. Talk about what will you both do in that situation should it occur…I think you’ll feel much more confident knowing there’s a plan to continue enjoying the moment without you having to be super hard.
Preparation is the key - turn up for yourself each day so when THE day comes so will both of you 
I would keep trying so you don’t have that tough situation as your last one you remember. Just take it one step at a time and maybe do things with her that you’re totally comfortable doing (maybe just masturbate alongside her and touch and feel).
Just confidently tell her you want it the [comfortable way for you] at the start because you “move at your own pace.” Make it seem like you’re totally in command of the situation, because you are and will be.
I believe in you
Oh keep dating! Read a book on the G spot so you can excite her in lieu of an erection. Sometimes while pushing hard on her G spot you will get an erection and can have at it. You get her G spot figured out and she won’t care!! She’ll want you anyway!!
Talk to her! Girls have issues too! Or work on yourself and keep dating.
I think you should date and persue sex only when you actually want to. My last girlfriend used to take my performance super personally. Which just added another thing to feel worries about and made sex an obligation. I’ve since been practicing bounderies and setting my own pace. My current girlfriend and I have found it can be helpful to take breaks ot just more time. She has helped a lot with me figuring out whether I actually want to have sex or if i just feel like I’m supposed to have sex at a particular time.
It hasn’t been all success, and being in a relationship definitely helps, but i’ve found that taking some extra time and requesting foreplay can be the difference between spiraling into self-doubt (for both partners) or giving her a chance to flex how irresistable she is.
Varying degrees of maturity out there, I think. The ones who appreciate you for more than just what you can put out are probably better in the long term anyway. Im
finding this is more of a journey than an immediate fix. Im starting to be ok and more relaxed about it.
Damn! Sorry, RA Cockroach, I get the SAME reaction from my wife of 34 years - if I blow it (and I do, too regularly now) she does get offended. Explaining it is terrible too, especially since I don’t know why it happens. Explaining what I don’t know is crazy. That’s why I am here to overcome my performance anxiety.
This is a pretty toxic opinion from my perspective.