Hetty58 My husband too was also a good friend, a good husband, reliable, hard working, supportive etc for years....until we had a mortgage, and had children and he had a period of being on strike for a while.
The stress and worry about money and responsibilities made him resent me and his sons. [His mortgage had been paid all the way through the strike though].
I've also watched a friend of 22 years become influenced by rich friends, a huge salary and noticed a degree of dishonesty with others, a lot of bending of the truth going on. As she rose to the top her views became very controversial, very 'woke', and she became very self absorbed. Then she was dishonest with me. I don't know why I was surprised really. So did she change or did the 'true' character come out? [I'd noticed but ignored the signs beforehand, more fool me].