Recovering from trauma is really hard. You come up with different games and conventions and tools to help you function because when it comes to trauma, medication can only do so much. Medication can make it easier for you to use those coping skills but they're not magic. When recovering, you can also celebrate the little things, the little victories. Maybe you did have to pretend you were the protagonist in a visual novel just to buy some milk but you know what? If it helped you buy the milk then that's okay.
It reminded me of this recent memory I had about my own childhood and being at my best friends' houses. The trauma was all still there in the back of my head and the anxiety of upsetting my mother even though she wasn't there and I had enough freedom to kind of enjoy being a kid but still having that anxiety looming over me. This was a good representation because she able to go out away from her mom (who is not dealing well at all) for a bit and she has a positive outlook and really wants to try and doesn't let mistakes freak her out or anything. But when she gets back it's just folding inside herself again and doing the minimum to survive. It's a good presentation of how messy and complicated having trauma is. Not even healing, just trying to exist and function.
If pretending you're a protag in a VN is what helps you accomplish a basic life function, then keep pretending because you will know when you can stop pretending, when you stop actively having to have that conversation and actively building that fantasy around you and just think... "oh, I'm out of milk. I gotta go to the store. 'Hey mom, I'm gonna get some more milk. I'll be back later.'"