Will I ever trust again??

My boyfriend is a compulsive liar. His sister says it, mother says it. And I see it all the time. I catch him but he swears he isn't, when the evidence is all there. A little back story... He lied to and hid a drug addiction , 3 times. First time, o would of never guess he hid it so well. He went to jail and that's how I found out because he was withdrawing. His sister said he got out and went straight back to it. Then he came out he is doing it again and there was just a bunch of lies why he was leaving the house and where he was and who he was with. He decided to go to detox ( only 3 days) because I kicked him out and didn't talk to him for a week. He realized I was serious. This was right before Xmas. His mom and sister said he showed up on Xmas <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">Eve</a> to his house waving a crack pipe. I found 3 of them in the house after detox and he swears they are from before and he forgot about it. Yesterday I found In His jacket the little bronz thing you put in the crack pipe to smoke it. He swears he has forgot it was there. I just don't believe him not even a little bit. I go to work and he's been off so he stays with kids. I ask him please do not leave the house because he doesn't have a lisence and I don't need him to get pulled over and I lose them. My GMA tells me he leaves at least 2 times a day leaving kids with her.for 2 hours at a time and gives her rediculous reasons why. And he tells me she is lying. He keeps telling me look at me I look normal I'm having weight. I'm always home with you. But I just can't stop thinking he's lying