I'm truly sorry to read this, I can't even imagine how heartbreaking that must be. Sounds like you're in a much better place now. My F-I-L was a very poor father to my husband, but he's thankfully had the sort of relationship with my father that he should have had with his own, so just thinks of him as his own Dad, so it all worked out, much like it seems to have done with your own M-I-L. On the plus side, he's convinced that it has made him a much better father himself as he had a good idea of how not to do it!