Said It's Over, But He Won't Accept It

So if you've read my other stories, you know I've been tossing around staying or leaving this marriage.  I made a decision, and finally laid it out in very plain terms with my husband.  He left for Fri and Sat night, but we talked on a phone a few times - mostly him trying to convince me that this is the turn around we need to move forward (puke!)   At one point he pointed out that he owns this house too, and I said, yes that's true and I can't kick him out.  So he asked if he could come back on Sunday.  I said sure.  Maybe that's nuts.  Maybe I am too nice.  I have been clear to him and told him I don't want to give him false hope, but I think that 10 years of putting up with his crap has taught him that I will just put up with more (which only makes sense).

So he came home yesterday and went down on one knee asking for forgiveness and another shot at it.  He says that he'll do whatever it takes, he loves me and the boys so much, etc. etc.  I believe he is very sincere in his love.  I don't believe he is capable of change.  

It's my son's 5th birthday on Saturday.  Then Christmas is a month away.  I don't want to stay in this marriage, and I don't think there is anything he could do to change my mind, but what do I do??  Do I start the process of getting divorced so he understands?  Do I say I'll give him to the end of the year, even if it's only a lie?  

We are still going to counselling - one more session really.  I was originally trying to make it to that session so we could talk about it in a controlled environment with someone who might actually have a little perspective.

Ack!!  I don't want him to pester me all the time about this - which of course is what he is doing.

Any advice?  You guys are so great to talk to about this stuff.