Good luck to you. I am going through it right now. Today has been a bad day where I am feeling a little lonely and wondering if this is my future but then I remember that I was lonely with him here too. I seen an attorney this week to draw up a marriage settlement agreement so I can buy my own home.
Keep calm and try to explain to him that you can't stay on the roller coaster anymore and that you aren't happy and your heart isn't in it anymore. Maybe separate for a few weeks to see how you feel but I found that when my husband was out of the house, I didn't really miss him very much. Good luck