Hi...I'm so sorry that you're going through this.
I can only really offer support and perhaps a point of view, but please bear in mind that you may see things differently because you have different issues than I do (besides the depression).

From what you say, I see this girl as only having been a friend to you. You may have wished for more, but she wasn't feeling it. In order to spare you additional heartbreak, she made the (very kind) decision to cut all ties with you.

Now, this was two years ago and, given that time frame, I think it's time to leave this all behind you. Difficult, given your obsessive personality (as stated as part of your dx). But not impossible.

So you DID lose someone special to you, but not because of anything you did. Confessing your love to her was an honest move on your part (not to do so would have been more difficult for you, you can be sure of that).

And as far as your romantic life...well, never say never. Things happen that we have no control over all of the time. And I know that for someone with OCD, this is a very difficult thing to accept. But just be open to possibilities. Sure you may get hurt, but is it fair to yourself to vow never to be in a relationship, just based on the POSSIBILITY of getting hurt? You'll miss out on some very good times....

If you were simply venting, then my apologies.