Welcome back,
Senata! 
In answer to your question, "Is it normal for adult children to make bad choices of friends?" I think it's important to remember that difficulty in interpersonal relationships is one of the many symptoms of BPD. A pwBPD is limited in her/his ability to maintain relationships with mentally and emotionally healthy, stable, people. So, while it seems your DD is making bad choices for friends, it may be that, because of her difficulty in interpersonal relationships, her choices are limited.
One of the toughest things about loving a pwBPD is standing aside and letting them live their own lives. I'm sure it's difficult when plans with your DD are canceled in favor of hanging out with others. What we are all learning here is to have the best lives we can have and working hard not to make our relationship with our adult children the center of our universe. You say you have only your children. It can be very lonely when our adult children are the only relationships we have and I hope you have others in your life to spend time with.
I hope you'll stick around and learn with us - things CAN get better for you and, in turn, for your relationship with your DD.
Have you had a chance to try some of the communication tools we are learning here? A good place to begin is by reading the post pinned to the top of this board,
HOW TO GET THE MOST OF OUT THIS BOARD Have a look and come back here with any questions, to talk about what's going on in your life. We are here to support you and we want to help. We get it.
I'm glad you found your way back here!
~ OH
