Advice for Engaging with Disabled ASD Adult

Hello :)

I'm currently at an internship site where I am working with various types of neurodiverse and disabled individuals. I'm really struggling with one client in particular, and wondered if there was any meaningful advice I could find by directly asking.

My client is a 30-something adult in assisted living, has ASD, ADHD, cerebral palsy, and intellectual disabilities/cognitive delay. She presents re her mother's concerns for her phone usage, binge eating and spending (takes her card and goes to the grocery store to sneak to buy tubs of chocolate icing and binges on them), struggles with other dopamine seeking behaviors such as screen addiction. She also uses her phone as self-soothing. She also has a lot of distress when her parents go out of town, even though she doesn't live with them.

The issue is, I cannot get past a few scripted small talk phrases with her. She either doesn't answer my VERY BENIGN questions ("What are you doing for the rest of the day?") or asks the question back to me, and then still doesn't answer. She doesn't really follow directions in session when I ask her do do an activity with me. She will play games that are fun in session, but that takes a lot of her focus, so it's more difficult to talk anyway. If she's bored for a second, she gets out her phone and it's hard to get her back. She gets a little stressed if she sees me cleaning up what we were doing that she's lost interest in, but doesn't stop her phone usage. She may ask, "What are you doing?" or reach back for a marker like, 'oh I'm still coloring' and I just put on a game we play on my computer that will get her attention. I've been seeing her since September of last year, I think so it's not early in our relationship. We color, we play games--together, side by side, virtual, board games, uno, etc.

Her mom wants me to talk to her about her recent binge/sneaking buying tubs of icing, but I can't get her to talk to me about regular things. She likes coming to see me, and is happy, but I've only got a few more months here, and I don't think even our relationship has been enough to soothe her nervous system, which is what I thought was happening since she did stop binging for a while without me saying anything. If she doesn't want to change, I can't make her. And I want to respect her autonomy. But her parents aren't always going to be around, and they're worried for her future health and emotional stability.