Husband lied to me for months

Before he was my husband we were dating for 2 years, he decided to join the army and was leaving for basic training for 6 months. 2 weeks before he left we had unprotected sex, then 1 week before he left he got into an argument with me (he had anger problems back then) over nothing so I said "if you don't want to be with me then don't" and left to go to work since I was already running late. He never hit me up or anything ever again before he left so I took it as we were over. A month later I found out I was pregnant with his child... I prepared myself to be a single mother because I thought that was what's best but I hoped when he got out we would be together again. 3 weeks before he was about to leave basic training he finally hits me up saying how he misses me and wants to marry me. He was the love of my life so I agreed to give it a second change. He told me he never dated or been with anyone else, how all he did there was work on himself even though there were signs that he was dating someone while he was gone. He kept trying to convince me it wasn't true & even had his brother tell me he didn't. I just decided to believe him so we got married and I dropped everything moved to a different state to live with him while he was in the army. Fast forward a few months to our girl being 2 months old, I finally found out for sure with proof he was in a relationship with a girl he was friends with while we were together. I confronted him about it & he tells me how crazy I am & to drop it.. I even saw proof of him asking his brother to lie for him in messages. His whole family lied to me. His mother, grandmother, sister, dad, and brother all lied to me about it...

I'm not mad that he was in a relationship.. I'm mad that he lied about it for months. I'm mad that I feel stupid in front of his whole family while I was pregnant and working so hard everyday to provide for my baby girl while I was pregnant. I'm mad that he said I was the only girl he had ever been with, thought about, or ever loved while he was away. I'm mad that he gave me chlamydia while I was pregnant when we finally got back together and lied and tried to blame it on me. How could I ever trust him again for lying to me for so long about it knowing I was probably the second choice after she broke up with him? I don't even know how I could ever be around his family without feeling stupid knowing they all lied.. it hurts seeing all his family saying in a post how he loved her on Facebook.. point of the story is how could I after he lied to me for so long.