Sounds like that big heart just got you a big knife in the back. People like this just aren't worth your time. I have a few of them. I mow, blow, go, and collect my checks. They're the ones that get cut whenever I have the time, and I don't even pick up sticks in their yard for free.
I have one guy that just bought a BMW but won't pay to have the dead plants in front of his house replaced. (That died from him over trimming them, too cheap to have me do it right) Another with a mercedes that has a tree growing in his old hot tub, holes in his deck, and garbage and brush in his yard that he won't pay to have cleaned up. I mow around it, no weed whacking near it.