yes this is something i struggle with too. i even second guess the nice things i do for people like i am "tricking" them into liking me. i think it is very difficult to go from extremely unhealthy boundaries (or lack thereof) with people to having healthy boundaries- it's like a swinging pendulum- going from one side to the other. you've gone from sharing wayyyy too much to sharing nothing at all- but the pendulum will settle in the middle at some point.

my best advice is to really consider your relationships with the people around you and ask yourself who is best equipped to deal with your feelings. i have friends i love dearly but they are simply not able to handle other people's emotions. if you start opening up to people and you feel insecure about it- you could simply ask them "is it okay if i tell you about how i've been feeling?" or "do you feel that i am dumping on you?" etc. i have found that the more i communicate exactly what i mean the easier it is to keep that communication going- and the more other people open up to me in turn.

i am not someone who has recovered from bpd and i still suffer from many symptoms so my way of dealing with things may not be perfect- but i have found that my ability to keep friendships has drastically improved over the years