My boyfriend's Secret

Hello! I have been living with my boyfriend for a year. Literally at 2am on NYE I found his tinder account and it turned out he had been messaging 16 girls from the 14/12/16. I asked him when he started he said 4 weeks ago so there are some I don't know about. He even got a girls number and saved her as Dwengue Santos (portuguese name) and her names Amy. They would whatsapp and he deleted the conversation so I couldn't see it. However she sent me the start of the conversation and said there was nothing more and he said there was. So I don't know. I've given him a second chance as this was the first time I've caught him cheating and it was New Year's <a href="">Eve</a> so I thought it's a new year tomorrow so one more chance. 
However he would delete his tinder when he came home from work and then he would redownload it on his way to work and talk to them through the day. 
I want to trust him but I'm shocked. When I found out I didn't cry I just threw up. I haven't slept in three days and honestly? I love him but he needs to earn my trust again. But I was so shocked because I genuinely believed he couldn't do something like that! I don't know how to cope or feel or what. Please help.