I think there are two main reasons I like this more than Generic Revenge Fantasy Number 87:
1. None of the party members want revenge, at least not at this point in time. They've all been betrayed by someone close to them, and they all hate that person, but more than anything else they're just looking to make ends meet.
2. They haven't been repeatedly kicked while they were down. They started on a downward spiral because they were stabbed in the back, but all of them fell to poverty because of an addiction they gained. Yes, those addictions were all ways to try to numb the pain from their betrayals, but it wasn't the world trying to make their lives personally a living hell just because they were nice people. That makes it feel more realistic than having literally everyone and everything team up to ruin them.
It helps to make it feel like they're just people who fell on hard times and are trying to rebuild, and I'm genuinely invested in seeing how far their friendships progress.