This sounds to me as though she's with someone who only keeps her around because the person has this idea that being with someone will bring them out of their depression. "I’m not your nervous feeling," "I’m not your drinking problem," She's basically saying that she's not this person's coping method. The chorus also enforces this idea, "All I have to do is shake shake
Keep your body still
Keep your body still" She's the one who's doing all the work, having all the fun, but the other person isn't putting any effort into the relationship. Then, "Don’t you realize you’re fine
Or can’t you see that you’re fine
And you know you’re still alive" is her telling this person that they don't need her.
This sounds to me as though she's with someone who only keeps her around because the person has this idea that being with someone will bring them out of their depression. "I’m not your nervous feeling," "I’m not your drinking problem," She's basically saying that she's not this person's coping method. The chorus also enforces this idea, "All I have to do is shake shake Keep your body still Keep your body still" She's the one who's doing all the work, having all the fun, but the other person isn't putting any effort into the relationship. Then, "Don’t you realize you’re fine Or can’t you see that you’re fine And you know you’re still alive" is her telling this person that they don't need her.