I'm currently in therapy and I see my therapist once a week which helps. It's DBT though so it's more worksheet orientated than talk therapy. I know talk therapy isn't supposed to be as helpful to people with BPD but I think it might do me some good once in awhile.
Other than that I have a couple of close friends I can talk to about this type of stuff. I don't like to burden them too much with it though.
I'm also online quite a bit on the BPD subreddit. More of a lurker than a poster but reading other people's problems does make me realize I'm not going through this alone.