I dunno Armygirl. I am a mom & have daughters. I know you are just getting settled in there with your folks again, which is a big adjustment for all of you.

Is it possible that your mom didn't want to react too much? Maybe she didn't want to upset you or freak you out? I mean, she actually made a joke, so maybe she doesn't know how to react yet. To someone who doesn't self injure, it is hard to understand.

I have one daughter who is so very fragile, I am Very careful how I react with her. It doesn't mean I don't care, am not concerned or want what is best for her.
It means I am careful how I react with her. That's all.

I couldn't love her more if I tried. I bet your mom does too. Maybe she is trying to leave the door open (so to speak) so that you can talk to her about it when you are ready.

Just maybe ...

All the best to you ~