Norah, it might be good to come up with a realistic limit or step on the goal, like "listen to at least three people's problems if they need it this week" or "Set aside so and so many hours this week to help mom and dad..." Or target a specific thing that you tend to do with your parents that bugs you and say "catch and stop self from snapping at parents five times" in a week and REWARD yourself. Punishing yourself will only feed the depression and you'll be more inclined to NOT meet your goals.
Limiting the time period makes it more likely you'll see your progress too Just ideas, hunny! Good luck!