['My sister had been feeling down after a breakup.']
I'm really sorry to hear that. What's worse is the best thing for breakups, the only thing that really helps, is time passing by. But the people who are hurting, in the moment, they can't really understand or accept that. So, you feel like you have to help and do something, when in reality it's probably best you don't smother them and that they have space. I hope she feels better, though.
My sister has been down in the dumps lately after a breakup. I made her come over to watch funny movies and eat popcorn and pizza to get her mind off of it.