Should I talk to my friend about this?

I would like some advice.

Last year, I introduced my good friend to everything health and fitness. I taught her how to meal prep, took her to the gym with me, educated her on fitness, etc. She took it and ran with it. She joined a gym, started meal prepping, and she began living her life with a health/fitness mindset, which I think is great.

However, since she has learned the ropes, she has excluded me completely from any physical activity that we used to do together (hiking, weightlifting, running, etc.). We went out for dinner a few months ago, but that’s it. Our communication is few and far between now. She’ll tag me in something on IG occasionally or text me a link to something I might find interesting, but that’s it. No “hey, how are you?” or anything. I feel left out. I understand that we both have a lot going on, but that’s been the norm for years. I don’t feel like that’s an excuse. People make time for what they want.

I invited her to my daughter’s birthday party on Saturday (my daughter views her as an aunt because we’ve been friends since we were 15). Part of me wants to talk to her about how I feel, but my daughter’s party is not the appropriate time. The interaction between us will likely be polite but not like it used to be. I feel like if I don’t address it eventually it’ll cause me to harbor more resentment. We’ve never had an argument in the 14 years we’ve known each other. Sometimes I feel like our friendship is surface-level and not as deep as I think it is at times. She doesn’t have very many close interpersonal relationships, nor do I, but she has been there for me to the best of her ability during a couple tough times in my life. It bothers me that we’re not as close as we possibly could be. Having the conversation about me feeling forgotten and used could put more of a strain on our relationship because I’m not sure how she will receive it.

What would you do if you were in my situation?