I'm thinking of stealing the rest of my girlfriend's narcotic medication while she is sleeping
Doesn't she need that? Why would you steal that medication?
I'm just thinking about it and I also don't think I'll do it.
Stealing is wrong, stealing medicine people need is more wrong. If your girlfriend is unlucky enough to live in the USA, she might not be able to afford to replace it.
It's not a big deal, it's not like she has to worry about money. I'm at our best, if she loses her meds she'll just go begging and getting for more.
But isn't she your girlfriend, don't you want to help and see her succeed? A couple is supposed to support each other, not steal and watch them have a breakdown. I think it's best for you to put these negative feelings aside and just help her.