What would you have done?

She was a HB8 asian standing by herself. I opened her by saying, "Could I get your opinion on something because you look like you don't get much attention!" She started laughing and I chuckled soon after. Continued with the opinion opener which was about mother's day presents and that transitioned into what shopping brands she likes to shop for. I negg-ed her a bit about kinda liking the same brands my mom likes. She took it in good spirit. She asked me whether I was [insert ethnicity] and I said yea I am why do you ask? She started talking about how she works with [ethnicity] doctors in plastic surgery and stuff. We transitioned briefly into Nip/Tuck the TV show and stuff like that. I could've done much more with the plastic surgery topic in retrospect but she changed topics and asked me who I was at the bar with. I told her I am here with three different groups which was kinda true. I was there with a friend and met his group. I approached two other groups on my own. I told her to imagine a venn diagram with three circles and told her im in the middle; immediately after doing so, I realized that statement was so cocky so I added on that I am in the middle not because I am the center of attention but just because I know people from those three groups. I know one school of thought is to advocate the cocky funny behavior, but I don't know why I felt I should be more humble with her. Perhaps because I had already entertained her in other ways. I turned the question back at her and she told me she is with three guy friends who are single and just hitting on girls and that she has a boyfriend. Boom! I didn't let it phase me and asked her whether she was winging her three guy friends and what makes a good wingwoman. She was unsure how to answer it. I used it as a DHV saying I have many friends who are girls and go to bars with them occasionally and they wing for me; what advice should I give them? In retrospect, this may have come off as pickup-y and needy (i.e. why do I need wingwomen?) Anyways, she said a girl just being there should be powerful enough. I didn't go into it more. She asked me what my name was (IOI?) and didn't wait for me to ask her hers. She told me hers on her own (IOI?). This is where things fall apart. I didn't know what to do next and I started letting the boyfriend thing get to my head. If she didn't have a boyfriend, I would've totally number closed on the spot. To avoid the awkwardness, though, I just told her "I am going to meet more people and, if you didn't have a boyfriend, I would've totally asked you out right now." Her response was "Aww, you are so sweet." In retrospect, I should've at least fb friended her and texted her later in the week. I don't know why I let the boyfriend barrier make me so un-aggressive. Definitely not going to let that happen again.