Oh wow, I am so sorry to hear about what you heard from those people. Look, the other posters here are right when they say there are women out there who are much more patient about sex stuff. Most guys don't last long on their first couple tries, because you've literally been waiting all your life for that one moment, and there's no way to know what it's like until you've done it. You will get better though, you just need more practice. I agree that placing so much emphasis on sex early in a relationship might be tripping you up a bit. That, coupled with your previous shi.tty experiences can't make it easy for you to let your guard down when it comes to getting naked with someone. Having said that, if you want to have FWB relations in order to gain more sexual experience, that might be a good idea. As long as you make your expectations known ahead of time, then sometimes that can work well for some people. If you aren't really into casual dating and you'd prefer to sleep with someone you're exclusive with, then look for people who will be respectful of your feelings, and about the fact that you're less experienced. We all start from the same place when we first start having sex, and how are we supposed to know what it's like until we start doing it? Porn gives extremely unrealistic views of what sex is like, it's not real sex that you see in those videos; but most women aren't looking for a porn star lover, they are looking for someone normal who is considerate and kind, which it sounds like you are.
I totally understand where you're coming from about your body issues. We all have things we like and don't like about our bodies and we all have areas where we feel inadequate. I don't think you should worry too much about that, though. More often than not, women don't care as much about size as they do about confidence in what you can do with what you have. I know you are nervous about sex because you lack experience, but if you're too stressed out about the logistics of it to have any fun, then how can you expect to enjoy yourself? I think you need to try and relax a bit, and try not to worry so much about your body and what you "lack", because I am sure you have a lot of great qualities that any woman would be lucky to find in a partner.
I think you should give up on that chick though. Even if she didn't intend to hurt your feelings with what she said, she still gave details about your body and your time together that should have only been kept between you two. If you had gone off and given details about her body and what she did, or didn't do, how would that make her feel? Pretty shi.tty I expect, and for her to say anything negative about you is just plain rude. There are plenty of women out there who value much more important things in a potential partner than what size his dick is, or how experienced he is. You just need to try and be a little more patient. Meeting the right person will make a huge difference, and I hope you find someone special who makes you feel fantastic.
"Caring is not an advantage."