Hi Prairie,
Well for one thing, it's fantastic that you found the strength to come out to people, both that you knew, and didn't know, so well. I think a lot of people are afraid to do so because of the stigma (I certainly am!) and I admire your bravery and integrity.
As for your reasons to worry about going out now;
a. It is perfectly rational to worry about having an episode. It happens. Your friends may also be worried about this. Have you explained what BPD involves and what might happen if you do have an episode? If they know about it, they can help you get through it, and you might have to worry less if you feel they won't be thinking "What a crazy lady" but "Oh, she is feeling bad right now, perhaps i should try to help her/leave her alone/whatever you told them helps you". Some of your friends may well be unwilling to help you, or listen, but then in the end they were never really your friends.
b. People could expect you to be just as outgoing as you were before. What it is important for them to know is that you didn't always feel like going out and being that way, so if you aren't hiding how you feel then you might not always be as extroverted as before. Again, some people might not want to hang around with the "real" you, but friends who won't help you through a hard time are no friends at all.
If you feel they don't understand your struggle, I would recommend you explain it to them. Maybe not everyone, just someone you feel comfortable telling. A lot of people won't understand something they haven't gone through, so sometimes they need a little extra help. It's fantastic you are such an advocate for poverty even through you ave not experienced it, but unfortunately not everyone is as empathetic and won't follow the rules of the world as we think it should be. All you can do is follow them yourself

Your friends may be scared and unsure what to do, which could lead to them leaving you out, just because they don't know how to deal with you right now. After all, BPD is a complex and sometimes difficult disorder, as we all know. Perhaps you could discuss how it made you feel when you are feeling a bit calmer? after all, you have been very honest with your friends so far, but they may not realise what they are doing as they can't feel how you do.
And no matter how things go, you still have all of us on here, and things won't always be this way!