I've been seeing my therapist for quite a few years now, and I still have a way to go, but I have thought about this a bit. Probably a bit dumb of me, but I like to imagine that I'd bump into her or we'd keep in touch, but deep down I know that's very unrealistic. She's highly professional and I can tell her career is her life, so I don't think she'd risk everything by befriending a client.