Agree with LH and Joseph. Don't worry about it. He will use any thread he can grab onto to point the finger and say see? THAT is why I have to leave and it isn't my fault, it's yours. This is honestly a script they all follow. i have to say it really helped me in my sitch when I realized this and saw the exact same words that were coming out of my H's mouth written down here in situation after situation. It's almost funny.
There's nothing you can do but focus on yourself and keep on doing what you were doing. Keep your head high and stay the course. Don't engage with him on it anymore either-- it's done. I don't think this is a major setback. Go do something fun for you and your son and stop thinking about him. Or, another thing that helped me in my sitch was thinking about all the positive parts of being on my own as opposed to the negative ones which were already occupying my mind (my kids being the biggest for me). In my situation, I was determined to stay in the house, so I started thinking about how I'd redecorate, take over the office, get rid of all his $hit, etc. And some things I just started doing anyway, like buying all new sheets/comforter for my bed. So... maybe spend some time cruising craigslist for apartments and see if there is something you like? Going through these exercises will help take the fear out of the unknown and help remind you that you'll be fine no matter what happens.
Keep up the great work, Artemis.
Me (46) H (42) M:14 T:18, D9 & D11 4/19 - 12/19: series of escalating BDs 9/20 - present: R and piecing