I'm angry

So I got back with my ex (which probably was my first mistake seeing as he dumped me for some random girl he met and felt such an amazing connection with and she ended up being mentally unstable two days after she convinced him to dump me)

But anyways he asked to borrow money (we've been back together 3 months)

Just to fill you in we dated 1 full year then we broke up because of this girl right and 3 days after he dumped me he was begging for me back literally begging. We are back together for 3 months now.

He asked to borrow $200 and I said that's okay. He said he'd give me half on Sunday and the other half on Thursday.

Well I got $80 on Wednesday. Still missing the $120.

He's like I've got the money I'll come see you and he keeps making excuses. But I have my car payment coming out on Monday coming and it costs me $125 biweekly. I'm freaking because I need it for my car payment

(Let me also add that normally I'm not tight when it comes to money but my sister was super sick a week ago and in hospital downtown and I went to visit her paid the crazy parking rates at hospitals had to get a hotel for one night in order to be closer to her because our mom had to fly in the next day but I didn't want her all alone kind of thing so my money situation felt short this week! And she fell I'll after I loaned him money)

Should I demand the money and tell him to stop jerking my chain or cut him some slack and miss a payment? Thoughts