I've had this problem with former friends, and I know just how stressful and horrible this can feel.
For me putting my foot down with them was the best thing in the long run. I felt like I was being bullied by this person, and I truly was being treated that way. They wanted to make me into this...person, who was more convenient for them to be around and deal with than being genuinely supportive/concerned or a good friend.
I got to the point where I felt miserable to be around them, to even think about them, and I didn't care if we weren't friends anymore but I just wanted to be treated like a person again.
So for me I stood up to them, spoke my mind and told them to stop being a a$$hole, treat me like a person or this was goodbye. I don't recommend fighting back at a first resort, but definitely tell them what you feel. If they brush you off, or don't think about how you feel, then there is something wrong if you're the only one in the relationship who is trying to be a good person to the other.
Hope this helps. Take care.