Basically, I'll be upset about something totally unrelated to LCM. I'll use being upset about her as a way to avoid dealing with the deeper issue. Or we'll have a session and I won't tell her what is really bothering me and I'll instead tell her how I feel about her. It's the opposite problem than with my other past T's. I am more comfortable telling LCM how I feel about her than I am about things going wrong in my life.

This^ makes perfect sense to me. It's a defense of creating a temporary reality where only you and she exist and all the other stuff goes away. It would be tempting even if you didn't see her as the Mom you've never had. I think it's not a bad thing because it can give you the foundation of safety to tackle other issues--one at a time.

Perhaps you've been concerned that she hates you because on some level you know drinking and texting would cause her to worry. Part of you knows that and may be using it as an unconscious way to get the emotional kickback of care. But unfortunately, you also know on some level that it's not a functional way to get the care that you don't fully feel worthy enough of to request directly. So maybe some unconscious guilt that then gets projected as worry that she hates you? She's right to be annoyed with that behavior.

Address the drinking before it becomes a habit. You don't need that burden.