My ex should split his stimulus check with me.
Why do you want your ex to split their stimulus check with you?
We both need to pay bills and this is this month's stimulus check.
You shouldn't demand money from an ex. Depending on how bad the breakup was, they may feel like they owe you nothing. Not to mention possibly insulted by the idea of giving money to their ex.
We are on great terms until I mention the check.
That's because you shouldn't demand money from your ex. I really think that if you need the money you should try speaking with your ex, and if they say no then try another way to find money.