She’s letting her 6 and 8 year old cuss and carry on at her house and then they come to your house and tell you extremely hurtful things about your place in the family and household. There’s a very good chance the kids don’t actually feel that way, and they are young and kids stay stuff they don’t actually mean all the time, but this is still not something I would take lightly. And I would not be trying to spending my own money on these kids if they were saying stuff like that to me. I don’t know if you’re leaving info out but if you’re not, I don’t think you’re doing anything wrong. Still, this does not sound like a healthy situation for you to be in.
If I was in your situation, I would leave. I care a lot about the happiness of my SK and im not at all saying that you don’t care about the happiness of your SK’s, it’s evident that you do. But if my SK he told me he didn’t like me or didn’t want to marry my dad, that would be it for me. Maybe SK doesnt really like me, maybe SK is just repeating what he heard at his moms. It wouldn’t matter to me. I would leave or at least move back with my parents.