Well, I may not be the best person to be giving advice (my bf just broke up with me because of my problems), this is what I think.

If you feel you're ready, then go for it. Get into it slowly and keep taking things slow. Really, don't rush into it. Go at a pace that will make you feel comfortable. I agree with VenusHalley, if you try to wait until you're stable you might be waiting forever. So if you feel comfortable enough for it, then it doesn't hur to try it out! You're right, rejection might come but it happens. As long as you know to keep your chin up, then things will be alright.

As for when to tell them your diagnosis... I would definitely wait until you're more serious and they know you better. I was just having this situation recently, wondering if I should tell my bf or not but he turned around and betrayed my trust by breaking up with me. You need to be sure that they're someone you can trust with that information.

What I did, is I let them know that I do have some problems with my mood and anxiety but I didn't make a big deal about it. Just kind of let them know without giving them the full story. I didn't do this until I knew them pretty well, though.

I hope this helps you!