How do those of you who are single parents deal with the the boiling rage that ex partners can cause?
My ds has just had a laugh about his dad saying that I "wipe my bum with £20 notes".
Now, I'm going to give him the benefit of the doubt that this was a jokey comment, but considering he had 5 foreign breaks/holidays/honeymoon in a 12 month period this year/last (and took ds on none of them), hasn't paid a days childcare, hasn't so much as bought a school uniform this year, told DS we would split his first HS trip between the three of us, (me, him, and Ds) I'm really struggling not to text his hilarious self. I don't want him implying to ds that I'm minted, because I certainly am not, and I certainly don't want DD thinking dad "pays" me and therefore helps me wipe aforementioned arse with said £20s.
He's a decent dad, has DD 2/3 nights a week, pays me £100 a month and pays sports activity fees £25 per month (although in his words, that's because it's something he wants DS to do 
) I know I'm better off than so many single parents (and even calling myself that feels a bit inaccurate) and we actually get along fine 95% of the time and are flexible with arrangements etc. but this one flyaway comment has me raking over every shit thing he's done in 12 years, and it's always the same. I can't just be pissed off at individual things, I stew over every other thing and want to list them all and tell him he's a shite dad whose life has never really had to change despite having two kids, even when I know he isn't really
How do you learn to just let it wash over you? I hate feeling so resentful and I know I should have put down better ground rules over the years, so I can't be arsed rocking the boat over this stuff now. I just want to learn how to let it all go.