Divorce guilt

I decided to file for a divorce a couple days ago. We have a very simple situation where we shouldn’t need an attorney. My husband is making sure that that changes. He wants to fight me all the way. I can’t help but feel like a terrible person for deciding it first. I feel like I am failing at life, I’m failing at being a mom. Am I missing something? Is this really a bad idea? My husband and I were together a total of 4-5 years and married for 2. Through out the 4-5 years he has continuously cheated, lied, talked to underaged girls and even slept with one. Almost got convicted btw. He also left me twice for underaged girls. He cheated while I was pregnant. Continuously used dating sites, Snapchat, any social media to pull girls. Treated me like absolute shit. My mom was on her deathbed and he would not come to the hospital to talk to me. I didn’t want to go far as if she would have passed while I was out I would never forgive myself. He told me he would rather hang with his friends. He’s given me HPV thankfully I no longer have it, but he does I’m assuming since he still has genital warts. He has done anything possible you can think of to hurt me besides have a baby with another woman. I finally decided it was enough. Our son isn’t even 1 yet. I feel like a failure but if I had stayed then I would be even more unhappier.

Now, since telling him I was filing he has told everyone lies about me. He’s told people I have a guy lined up and I’m cheating during this divorce. He’s also use our child to scare me into thinking he will get full custody. I know he’s hurt and upset. He begged me to give him one last chance but as you can tell I’ve given him more than enough for one lifetime. I just wish he would let me go on my way easily. But of course not. He’s just put me through absolute hell. I can’t even be mad at anyone but myself.

How do I get over this guilt! I know I will be happier after it’s said and done but he’s dragging it out out of spite just to stress me out and make my life hell.