Sprite-
You are certainly not a basket case. It sounds more like you just woke up from a very long sleep.
I don't think you realise the dynamics of what you have done. You have put yourself in quite a good position, and all you need to do now is click your fingers, and wait for the magic
What on earth am I talking about?
What I am saying is that you FINALLY gave him an ultimatum, and reading what you say about his response, especially his willingness to buy a farm etc., you have won!
So what you need to do is make a small list of priorities and get him to focus on no more than 2 or 3 at a time. Any more than that will defocus him. Don't worry! - When he has mastered every thing on your list, you can knock of the first 3 items, and put on the next 3. You need to explain to him about the space thing, and not following you around the house, and questioning you. You need to really explain that you need x hours a day without him breathing down your neck until you get it out of your system. (It is interesting how at one time you wanted nothing more than his company, and now you don't want it. That's resentment for you...)
I'm not suggesting you turn into a nag-bag, just be firm and reasonable at the same time. In return, you need to let down your wall, or he will eventually realise there is nothing in it for him - so don't blow it. Also you should praise him when he gets things right.