How do you deal with watching your Ex fail?

I'm sure alot of people on here would tell me to laugh, or appreciate karmic justice, but i cannot. For four years i supported my ex and was there to help her through tough times, but one month after d-day she called and told me she is drowning in bills and was concerned she wont be able to make ends meet. I'm not helping her pay her bills after she cheated, but it's really hard to watch her struggle. Does anyone else deal with this? I'm having a hard time just letting someone i used to love struggle and drown.