AIO bf addicted to gambling and is frustrating to talk to about it

Think my bf of 3 years has become addicted to gambling this year. He became unemployed in march and went almost all year with no job, relying on sports betting and unemployment to get by. He also has debt and wasn’t getting that off at all. He WAS managing to get by until October, I had to loan him $1000 around Halloween for bills and he promised to get it back to me in 3 weeks because he had a job lined up. He started his job the first week of November. The end of November comes around and I haven’t seen a dime or heard a word so I’m frustrated and we end up fighting about it because he wasn’t being understanding at all. He does up telling me he needed til the end of January.

I ended up folding and accepting it because I know he’s catching up on bills and getting back on his feet and is moving out soon but I’ve had to sit around and watch him place sports bets almost daily since. They’re $10-$20 bets and it adds up. I brought it up today after letting it eat at me because it’s frustrating to see when he owes me money. At first he understood, said he shouldn’t of borrowed from me in the first place and will pay me some tomorrow and work to get it back ASAP but after I mentioned how it’s unfair that he sports bets when he owes me money he got offended and a fight broke out.

I may be being kind of harsh but I’m so fed up and he never understands where I’m coming from instead will just blame me and get defensive. Say things like “why are you with me then”. I’m just so frustrated