Going through divorce

I am so sad my husband cheated on me and wants to be with his mistress. A ton of questions in my mind. He thinks she is the best. She is married and is only stringing him along. She doesn’t want to divorce herself. She has straight up told him she wants a good and comfortable life and he doesn’t realise she means money. Or he does. That's why he wants to give me and our handicapped child 600 per month and says I should get a better job if I want more. This man earns 16k per month after taxes. After taxes i earn 2k per month. The benefits he gets per month in his salary for our child is 700 per month. I am 20 years younger than him, I have postgraduate studies, converted to his religion, but apparently nothing matters. She is exceptional he says. In his mind she is this wonderful human being with brains, beauty and coming from a family he respects. Of course why would I want a man like this? Why is it so difficult to accept this? He still wants to have sex with me, have me around, take care of him, but not married to me. He is just more in love with her he says. I don't deserve this. I have to let go. I am so sad for my child. Our child.