I am having difficulty being intimate with my injured wife

Been together with my wife now for 22+ years. Have had her in my life longer than I have had without her. Due to her hip, Avascular Necrosis, she is in incredible pain all the time. Walking is almost impossible without a walker or just me helping her in a wheelchair.

But she still desires me, wants to have sex. We have had a very active one up until this point.

She is hurting mentally because we are not able to have sex as much and now going on three weeks. I still desire her but have a hard time staying in the mood when I know she is hurting. Or thinking that she isn't in pain currently if I move or do something wrong, lose myself I will cause her pain.

But by not being intimate with her is hurting her heart mind and soul. She thinks I will cheat because of this.

How do I overcome my fear of hurting her and just let go so we can be intimate again?