If I'm going to be lonely - maybe it would be better to be alone.
as far as I can see from what you have said, you are missing out on social occassions because he will drink. If you were not with him, you could go? so not that lonely?
perhaps you can go now? I don't know your situation, so I ask you (and you don't have to reply: just think about it) what happens if you do go out and he does drink?
what is the awful ending to that story that means that you have to stay in to prevent it?
I am quite clear that their can be awful endings to that story, and ones that you might not want to talk about, and in which case do what you need to do to be safe first, but also think about whether this is the life you deserve.
if the answer is not that, if the answer is that he drinks, gets drunk, falls down, passes out, end of story. Then perhaps try to understand why you are isolating yourself to prevent him doing what he wants to do: it might be good to think about these things: when did you become his alcohol monitor? is it a job you enjoy? Should a grown adult have the right to use/abuse their own body any way they see fit?
I know the answers aren't necessarily simple, I isolated myself for a number of reasons: he would not stay sober enough to look after the children and I didn't see how I could get a babysitter if he was in the house. He had been physically and sexually abusive in the past and although these behaviours had stopped, all the triggers and behaviours leading right up to them hadn't so I was afraid they would happen again if he got to a certain level of drunk (and I HAD to know how near that level he was) and modify my behaviour accordingly. I was never really worried about his health (I'm not that compassionate, I always figure that's their own thing) but I see that lots of others here are, nor was I worried that he wouldn't come home (I prefered if he didn't, but i couldn't stand the not-knowing that he might walk in any minute, and I had to "steel" myself before going in everyday).
much of this I only understand now, I am slowly discovering or understanding or revealing my own reasons, because in the midst of it much was automatic and learned and subconcious. So don't expect all the answers now, but perhaps if you could start to finish that sentance:
I turn down invitations from friends and don't do what I want to do because every time I leave the house - he gets drunk.
and *I need* him to not be drunk because........
((HUGS))