<human>: I recently got engaged to my fantastic boyfriend. We started discussing wedding parties, and now I have a question I would love some perspective on!

I met my friend Ashley in medical school, 8 years ago. We weren't super close, but the class was relatively small, and we knew each other pretty well. I went to her wedding 4 years ago, but wasn't in the bridal party. We ended up going into the same specialty and matched to the same program. Two other women, Beth and Caroline, also joined the program. The 4 of us became friends and have been pretty close for several years now. We have a group text message, and we all talk several times a week- a lot about work, but about life, as well. I still feel closest to Ashley, though, and she's the one that I hung out with the most outside of work, and that I talk to the most about personal, non-work stuff. 

Beth got engaged a few months ago, and asked all 3 of us, Ashley, Caroline, and me, to be bridesmaids. I am thrilled to do it, but I feel like she may have asked me, and possible Ashley, out of obligation, because I know she is closer to Caroline than either of us. So before Beth asked me, my plan was to ask only Ashley when I got engaged. Now, I feel like I should reciprocate and ask Beth, as well, which means I would really have to ask Caroline, too. The only reason I wouldn't is because I don't want a huge bridal party, and there are people I'm closer with than Beth and Caroline. Do you think it's an all or nothing? Either all 3 or none of them? Or is it ok to ask just Ashley, even though Beth asked all 3 of us? Thanks!

Can you summarize the given text in a few sentences?
<bot>: Was asked to bridesmaid for one of the girls in my friend group, do I ask entire friend group to be in my bridal party?