My advice is not to look for a relationship and wait until it hits you on the head, but then, yes go ahead. The person you commit with should already be aware of your issues and have displayed the capacity to handle them and also to help you learn alternate ways of thinking. Note: This would also be the advice I would give someone who did not have BPD but had previous problems with relationships.
The reason I say this is because you will be spending a very long time working on your pattern of thinking even with therapy. Maybe your entire life. In that time, you will need to practice on real people, and eventually a real relationship. Just be more cautious than you have been so far, by saying no more.
Oh, and welcome to PC!