Hi! Welcome to PC!
I deal with depression, chronic pain conditions and a Systemic Exertional Intolerance Disorder (SEID aka CFS/CFIDS). I understand some of where you are coming from. A little doesn't seem like enough and a lot sets us back!
I think it comes down to acceptance.
I have been an avid athlete earlier in life. When I became ill, I was truly heartbroken, as I loved being very athletic and very active. It is now over 30 years later and I still miss being more physically active. However, I do work at accepting my limitations. Why? Well, if limitations have been adequately challenged and are "real," then it's wise to accept the limitations, instead of hitting my head, repeatedly, against a brick wall!
I try to boost my self-esteem in other ways. I try to find more sedentary ways to contribute and to feel okay about myself.
It's easier said than done, I know. Yet, it's also helpful to stop beating myself up for what I can no longer do.
Self-acceptance is my word of the day today!
I hope you will find a place of self-acceptance, too!

WC