Hello Ki3
First off, let me reassure you that you aren't alone, this happens to many of us growing up, crohns or no crohns. I didn't have my first relationship untill I was almost 17 and there were times where I felt like I was the odd one out or like no one would ever want me (I wasn't diagnosed with crohns, but was diagnosed with other things and had symptoms from age 15).
The important thing to remember is that you are still young, I know thats easy for other people to tell you, but its true. Many teenagers don't have relationships for a number of reasons. My sisters and my brother didn't start dating until around the same age as me either, and now we are all in happy, solid relationships. It isn't about the age you start, its about who you find. Your neighbour may have 'boyfriends' but that doesn't mean that any of them will turn into a mature relationship when she's older. There are no set rules for any of this, no one says we have to start dating at X age, and honestly, a relationship that naturally forms and falls together, is so much better than one thats made, if you get what I mean.
You seem like a mature, sweet, caring girl, and you will find someone who sees past the illness. It might take you a little longer to get into the dating seen than some of your peers, but that's not always a bad thing, and its certainly not a reflection on your personality. Try to enjoy being young while you can, especially now you seem to be getting remission (I hope?), have fun, spend time with your friends, just be a teenager, all the other stuff will fall into place when its time.
Ps, remember you are always welcome to contact me if you need to.