I am just over 2 years doing all of this and it's getting better by the day. You will just get to a point that you will stop focussing on him and you will start to focus on yourself and your kids. That is when going to no contact really makes things better. Also, that is usually about the time our spouses "may" take notice and start poking around.
So, you really have to try to not focus on him. I know it is not easy, trust me we all know. When you first start the disconnecting process it is extremely difficult but I can tell you it does get easier.
I know hearing all of this does not make you feel better at this point but just know that we were all where you are now and it WILL get better.
I too have ex in-laws that turned against me. That is very difficult for me to take as well. I just stay as clear away from them as possible now.
Keep writing as we are all here to help you out.
Me/W: 46/36 D7.6/S6 T/M: 7.5/6.5 Bomb 12/05/07 D final: 03/03/09