I feel so broken (porn, cheating, and lies) *long story*

I do not even know where to start. I am not very good with my words, but I an hoping I can describe things as they are and not leave crucial information out.

So me and my fiancee have been together for almost 6 years. We have two amazing daughters, one is 4 and the other is 10 months (going to be on the 11t of this month). I gave birth to her this year in February. Everything seemed perfect. We had a perfect little family. One day before my youngest turned 4 months old, i walked in on my husband having sex with his coworker. He was supposed to go golfing after work on a Saturday while my mom was watching the two girls and I was getting my hair coloured. I called him during the early morning and told him how much I needed him because me and my mom just had a huge argument. I told him that my mom is not coming with me and that I am in a terrible mood. I cried on the phone and I must have talked to him for about an hour. Anyways, he kept telling me he missed me and loved me and all that. So at 3 pm he was supposed to leave work and go out with his friend and shoot some balls as he says. For some reason, I had a bad feeling. I kept calling him to let him know I am done with my hair and on my way to pick up the girls. He kept being weird saying stuff like I wish I would be there now and I feel so bad. I didn’t understand why he felt this way, i mean he could have just leave “golfing” and come home. I thought he was weird so I checked his location on find my phone app. It turns out he was at a random house. I kept calling him about 20 times while he didn’t answer. I went to the house. I saw my car on the driveway. I checked the trunk, and there is his golf stuff. I told myself i am so stupid he is playing play station. I called and called and called. Mo answer. It was after about 20 minutes and a 100 of phone calls when I decided I will go and knock on the door. As I walked up to the door feeling faint and about to puke the door opened. I saw him having sex with this older woman. She was just trashy looking with a kid on her own in her 30s. I am 24 btw. So I lost my shit as most women would do. She casually started to make herself a cup of tea. Wtf?! Who does that. Gosh sorry I am getting worked up again. So me and my fiancee went home talked, argued, cried. I decided I will take the girls on a vacay for a week and it gives me time to think. As soon as I left this co worker calls my fiancee at 5 pm on a saturday to ask about “work”. The company closes at 3 pm on Saturdays and there was zero reason for her to contact my fiancee. My fiancés boss agreed with me too on this. She proceeded to ask if he missed me and of he was bored alone. Again, my blood os gonna boil. When I got back he didnt tell me about this 15 minute long phone call, I found it out when I checked the bill. I went to his work and confronted both because they both were being untruthful. This woman starts yelling at me at this point calling me crazy and wanting to fight. My fiancee did nothing. I told him to get out of my life. Eventually word got around and this woman got fired. I told my fiancee that I will work on the relationship because we both deserve a second chance and my children deserve a complete family too.

Fast forward to now, I know he has been watching porn on a daily basis. He tells me he needs to unwind in the bathroom for half an hour. I get it. He needs time to be alone after work and relax. But I stay at home all day every day with two kids. All i look forward to is him being at home and spending some quality time together. Then I walk in on him watching porn videos of different women. He never initiates sex with me and when we have sex he doesnt do a thing. He wants me to please him but he doesnt even touch me. Like ever really. I find it heartbreaking to know that he rather puts effort, attention, and energy into watching porn than me. I told him I am fine with it as long as it doesnt take away from our sex life. But at this point, it does. He told me its hard to have sex with the kids around. We live with my in laws in our separate basement. My sil would watch the kids for me, she knows about our problems and she always says she will take them up so we can have some alone time. He says its difficult but it wasnt difficult to lie to my face and go over to another womans house with the intent to have sex and cheat on me?! Also, when i confronted him about porn he lied to me. He looked me in the ye and told me its not porn its a car video. I find it so hard to get over the fact that he lied about something small. If he lies about this, does he lie about everything else?

Unfortunately, I have developed twitches and ticks as a result of postpartum depression and being cheated on and lied to. When I am stressed I start to jerk my body. I feel so broken and feel so unworthy of him. I feel like I failed and it is my fault that I was cheated on by my best friend and the love of my life. I have spend my entire adult life with this man. I know he loves me and I love him too but his selfish ways are becoming a real problem. I told him to ask insurance (through his work) about therapy due to my twitches and ticks and he did but never got an answer. I told him if it would have been important he would have asked whoever is in charge of these things and would have went after that person to get an answer. I love this man so much and i know he loves me too but he is stupid.