Why doesn’t he understand??

So this is long.... bear with me.

We recently bought a house. This is only the second house we bought so we didn’t really know about the earnest money thing. We found our dream house but didn’t quite have the $1,000 earnest money to put down but wanted the house before it got bought in this hot buyers market. Long story short my husband asked his grandmother to loan us some money because my family has helped us out a bunch in the past (not because we’ve ever asked, this was our first time asking for money, but just because that’s how they are). Well day after closing his grandmother is sitting on the couch in our new house asking about getting paid back. Well without going into too many details we ended up not making as much in the sale of our house and one company was holding $1,000 of our money while our insurance agent screwed up by not cancelling our insurance policy like he said and we got billed $312 we weren’t supposed to so we are basically just waiting around for $1312... we also have two kids and I’m pregnant so unexpected medical bills on top of everything. Even knowing all this his grandmother is hounding us for money immediately so they can “go to a concert”. Knowing we will have it as soon as we get paid back but saying at first she needs $200 rn, then $300, then $400! Thankfully we got the $1,000 released and was able to pay her back but she still hasn’t cashed the check and had the guts to call and tell my husband today she was shopping at the mall and wanted to buy him new boots (several hundred dollars) because his don’t fit great and she can’t stand to think of his feet hurting... and my husband who is typically my bf and we always think the same- rarely fight and literally finish each others sentences- he can’t understand me being upset with her! I’ve had a rough emotional day. Actually had a bad panic attack and almost couldn’t even pick my son up from school because I was so upset and he chooses to fight with me about this?!? He doesn’t see how her behavior makes no sense! Even a loan from a bank wouldn’t demand $400 immediately after the “due date”. I know she didn’t have to lend us the money in the first place and I’m grateful for that but my family could have easily done it and they would never pressured us to this extent that we are scraping to buy groceries for their great grandchildren because of all these unexpected expenses (excess of $4,000) that came up.