hello needtobealone,
I didn't mention in my first post that I am a man, so I maybe I can also give a male perspective.
There is no way at all that you are a bitch, as you say. On the contrary, you are coming across as an extremely thoughtful and brave person. The easy option is always to keep the status quo but you are not taking that route and that is all the more to your credit.
It sounds like you took a very adult route tonight, talking to him and then finding a way for him to give you some space. Credit to him too, he is showing some courage by giving you the space you ask for, added to admitting to his parents that his marriage is on the rocks.
I hope that you don't end up feelng too uncomfortable with the space he has left you at the weekend. Of course it is tempting to drink yourself to oblivion but the same problems will be there when you sober up. IMO when you have been in a relationship for a long time, the thought of being alone is the scariest part. Obviously I mean long term but the same applies in the very short term now and finding yourself alone this weekend may also be daunting. But if you can, try to take some time to gather your thoughts. My suggestion earlier of speaking to the Samaritans stands firm. They are not in your family or friends, they will listen and not judge you, and give you time to formalise your thoughts.
All your husband can ask of you is that you are honest to him and, from what you say, it seems that you have been very open with him. By looking after your own needs and asking for space you are also looking after those around you too. It's the old adage of if you don't look after yourself first you cannot look after anyone else. By taking this brave and adult stance, and asking for space, you are ensuring that you do not do something rash - hence you are also looking after those around you too.
And remember, he will find his own resources too to look after himself, you just worry about yourself for now.
Hope that is of some help.