@dezzy Oh, hon! I can relate SOOOOO MUCH! I'm disabled. I have been since my early 30s. My kids were still older children and teens then. My in-laws and other family members/loved ones have done so many "firsts" for or children and grandchildren.
I comfort myself in this way...
AT LEAST, the kiddos got to do something. My sister taught 2 of our children to ride bikes. Other family members have taken our kids fishing, hunting, camping, etc. I'm SO GRATEFUL they got to do these things! It
HURTS, though. I'd rather my children and grandchildren get to do these things, even if I'm the one who can not give them that experience. Again...
IT HURTS!!! It's better than them not having those experiences at all.
Try to focus on the kiddos having experiences regardless of who does this for them. You can make more core memories in other ways. Please, don't be so hard on yourself!
EDIT: Four of my kiddos called railroad crossings "RRX BIG BUMP" because of the signs near the tracks. I can't tell you how many times I drove around town just to cross over all of the train tracks I could find lol. They LOVED the trains and ADORED the bump of the car going over the tracks!