There can be genuine concern when addressing a loved ones weight issue.
Of course, be careful not to be a hypocrite, cherryberry, are you in good health? Are you at a healthy weight?
No one would listen to a ski instructor that cannot ski...
Cherryberry, you need to fix your relationship with your daughter first, then you should have a open hearted discussion(s) about your concerns and tell her how you can help her achieve better health. You’ll need patience, and you may need to walk the path along with her. You’ll need to boost her confidence and not degrade it.
Good luck.