I think you handled things well. You left and held your reaction out of her reach. You took a walk - good. You recognized you were tired and crazy - good - more sleep needed.
I know this is hard to learn, but we cannot control what decisions others make. We just do not get control others anymore than they get to control us. Once you really understand that thinking you can develop other ways to respond to her and your own feelings. If you were good friends, could you talk to her like old times? What kind of response would you get? Try to understand that being her best friend might mean letting go a bit and seeing if she returns. Maybe she is afraid of going out on her own, support her, let her know it is ok for her to try and find out whatever it is that she needs to find. And you might need to let her tell you what you need right now and how the time apart might be useful to you. Am I too way off here? Just ignore it if I am. I kind of have a thought I was trying to express but not sure it got there.
