Hey Boz,
I'm really sorry you're dealing with that! From a working lady's point of view, it's not an uncommon problem. I've met quite a few clients with various ED issues. (I can't imagine laughing at someone for it - that is just awful!) Usually with a bit of communication and creativity we can still find a way to have a great time.
And just from a women's perspective, you definitely shouldn't push people away over this. Get some toys, or focus on your skills with your hands or mouth. Most women are used to men finishing before them, finishing early isn't a problem if you still take care of her afterwards