Sounds like you might have problems with affect regulation (aka emotional self-regulation), OP. This means that both positive and 'negative' feelings can be anxiety-provoking and difficult to contain for you. Not only that, but your confidence in your ability to affect other people's emotional regulation is likely to be low. In childhood you probaby had no-one who consistently accepted and taught you to manage your feelings (as opposed to your feeling states often being rejected or criticised and neglected). Also, you would've felt that you had no control over the destructive and/or anxiety-provoking feelings that certain other people frequently demonstrated/acted out. Bottom line, you became frightened of your own feelings and other people's, to various degrees. It mightn't have been safe on various occasions for you to be happy, excited, joyful, experience pleasure, or even have preferences for one thing over another (ie. make choices for yourself) without suffering some sort of inhibiting or discouraging or prohibitive behaviour from others. As an adult you can't trust your feelings, whether good or bad, and so you tend to avoid experiencing them by dulling or deadening them with alcohol. Another possibility is that when you do feel good, part of you doesn't trust that it will last or be enough to enjoy, so you seek to enhance it with alcohol. But chances are that results in a loss of control which causes problems in your life.
I'm not an expert, just have a little training and experience, but if you were my client I'd be thinking along those lines. I'm guessing you've already looked at how drinking is a way in which traumatised people can dissociate from feelings, and for some of us 'good' feelings can be threatening because it's as though any feeling can signal a loss of control. I wonder if it has something to do with us concluding when we were small that feelings of pretty much any kind can feel like they're caused by other people, rather than originating within us as a response to what happens around us. And so, again, we can feel anxious about good feelings too, because we're not taught that feelings are an inner response to events and people, not something that is put into us from without ourselves. This basic misapprehension of what feelings are and where they originate becomes ingrained in our unconscious perceptions of our interactions with others. We feel like most, if not all, of our feelings are projected into us by others/the world (ie. they cause our feelings, cause us to have feelings of various kinds) and so we try to get rid of the feelings by dissociating in certain ways. That's one possible explanation and I find it quite useful. I grew up believing that pretty much all my feelings were somehow caused by situations, objects or other people. I didn't understand my own role in having feelings, so I couldn't own them. I actually had no concept of owning feelings, at best I believed I was just at the mercy of feelings. But mostly I thought they came from outside myself, caused by other people. Now I understand that they're a form of innate intelligence that resides within me, but I still struggle with them at times because my default position is to 'disown' them. I mean, I used to think I must be bipolar if I got excited about something because it felt so overwhelming and made me fear I was mad, out of control. All kids need careful containment - ie. firm, nurturing boundaries - to learn to manage and regulate feelings, so that they learn to feel safe to have and express feelings like happiness, excitement, frustration, anger. If you don't get that as a kid, feelings can seem dangerous, even good ones. You can conclude that even having happy feelings makes you vulnerable in some way.
It's a cliche these days, but mindfulness can help. And therapy, of course, with someone who can teach you techniques for recognising and acknowledging various feelings in your different life situations, and then how to tolerate and regulate those feelings for yourself in healthy (ie. not self-defeating and self-destructive) ways. It's life-saving work but it has to be done and then become part of how you live. In my experience it doesn't guarantee an easy life but it definitely helps us to feel more in control and more trusting of ourselves, and as a result less likely to run away from our feelings, or should I say ourselves. Consciously accepting how I feel, then making a choice about what I'll do while I'm having that feeling. (As opposed to rejecting a feeling by numbing it, or manipulating it to enhance it in a misguided attempt to make it last forever!) The duration of many of our feelings can be so fleeting, if we let them pass. Letting them pass (breathing, making healthy choices in the moment) is the control we can have, anytime. We learn to trust them.