It's lovely to hear from you, I've been wondering, and hoping all was well. However I am going to maintain my warning stance.
If he was serious about change he'd have:
owned that he is an alcoholic;
stopped drinking, possibly under medical supervision;
be in an ongoing support programme;
he would not be starting a relationship, because he is already in a relationship, an all-consuming one, with alcohol, and he needs to end that before he is able to enter a healthy relationship with anyone else.
His friends are desperate for someone else to take responsibility for him.
You have been designated and offered yourself up as fixer, nursemaid, and reward for good behaviour. I know you mean well, and you have shown awareness and candour here. You have indeed set clear boundaries. Paradoxically that's a warning sign here. Your own history, psyche, relationship with alcohol, and identity as a sometimes party person has drawn you straight into co-dependency.
Those boundaries are HIS boundaries, which he has to figure out and set and sustain for himself if he is to tackle his alcohol dependency. You cannot do that for him, with yourself as the prize; and that you have done means you are already a problematic element hindering his recovery.
Your role in this is also bad for you, I'm sure, if you delved into your own life.
Keep you wits about you, please keep posting here for reality checks (if you can bear us), have some therapy sessions to explore why a relationship dynamic like this is appealing to you. Wishing you all the very best x