Libertine - I'm really concerned by your post. I'm also confused as to you being half cut, I take it you're still pissed from last night?
The remark you made about losing your DP 'at this rate' didn't read as though you were worried or sad, it sounded like a fact you've already accepted? Surely you don't want that?
You say you have a really heavy weekend coming up that you'll feel guilty about on Monday. It sounds as though you've resigned yourself to the fact that you'll be drinking all weekend?
As Faire said, could you maybe reign it in, drink soft drinks/water in between the booze or not have so much? Eat lots of stodge too? No-one has to know if your Coke has no rum in it! 
Nothing I can say will stop you from drinking because from what you've said, it's going to happen with it being a weekend of partying and celebrations. The thing that's worrying me is that you don't really seem to be worried about what you drinking like this is doing to YOU, to your life and to those around you, your DP for one.
I know I'm being harsh here but I'm not sure if you do want to slow down or stop? Maybe not today but longer term? It's as if you want to self destruct :(
Do you see just how bad this could all go? 'Play the film through to the end' is something that MIFLAW (a recovering alcoholic used to post here) .......basically, watch the whole scenario unfold in your mind, from the very first drink, through to Monday morning. Can you imagine the emotional and physical damage drinking so heavily will do to you, and others?
I'm really concerned that you are going to get hurt, or lose your DP, can you try and slow down for today at least? Please Libertine, try to look after yourself more. You are worth it, you are loved and your DS needs you.
Sorry for if you think I'm being unsupportive, that's not my intention and I'm sure someone else will say what I'm trying to much better but please, be careful xx