Go to a lawyer; don't start worrying about who might owe who alimony. My husband's ex-wife wanted alimony for life and that has to do with various county laws so my husband's lawyer had him move to the next county over (which had never granted alimony for life) and buy a house and then file first. Protect yourself and your children; if he's a sourpuss, he's a sourpuss, you don't have to live with that.

Why would leaving their father impact the children's relationships with their sisters? The sisters know what their dad is like, etc. The ex-wives certainly know. I don't think anyone is going to be torn between someone pleasant (you) and Mr. sourpuss?