I don't think you should go, it doesn't sound too safe for you with your mobility problems. Is there anyone you know who you could gift the holiday to?
It will soon be three years since my husband died, and I haven't been away anywhere on my own since before Covid. I thought about going back to places we had been together, but, as you mention, I think that would make me too sad. So I have made a decision only to visit places that I've never been before, not to return to old familiar haunts. I'm going on a widows' retreat in Scotland in October, quite looking forward to that, but nervous about travelling alone.
Maybe you could consider a specialist holiday, something like painting or singing, where you could be part of a group?