Would you lend money to family?

Back in early Dec my mom needed me to help her get her car cuz it got towed from her neighborhood cuz she forgot to move it from a visitor parking spot which is permit only - it was left overnight. Anyway, so she called me to ask for a ride to pick it up, well when we got to the Tow Lot - they didn't accept Amex and her other CCs were maxed, she had no cash and they didn't accept checks. So, I ended up loaning her $150, money I didn't really have because I just paid a bunch of bills myself and wouldn't get paid again for 2 more weeks - WHICH she promised she would pay back the following week. Anyway, so I really wouldn't care to get paid back, because my mom has really done ALOT for me over the years, BUT my husband is really pressing me to get my money back. Here is where the issue lies, He says if we agreed to it was a loan then she should pay you back, True! I agree, BUT he never had the close knit family relationship with his family like I have. He never had a relationship with his mother, ever. I keep telling him that I will ask my mom about the money, but I won't pester her for it, yet he keeps pestering me about it. So the other day I decided to ask my mom about the money and if she could at least pay a little something, because I know what she's going thru now, basically playing catch up after a 3 week hiatus because she needed cataract surgery really bad. But when I asked my mom about the money, she kind of got defensive and said that she needs to add up all the money she's lent to me without ever asking for it back. Of course I have no room to complain, and I definitely will NOT let money drive a wedge between my mother and I, but what do I say to my husband now? He is really pressing me that I get that money back and whenever we talk about this issue it some how turns into an argument. Thanks...