Is he doing cocaine...again?

My fiance and i have been together 3 years. From the start he's always said hes never done cocaine. After a year or almost 2, he slipped that he has tried it.. I have had suspicion that he has been around it since then (given his friends are very bad influences and do it openly). On new years i found a little bag in his pants after watching him go in and out of the bathroom several times. He called me crazy and was yelling that he doesnt have anything while i was checking his pants.. But then i found a sack. He swore on our 2 month old babys life that it wasnt his and that he took it away from his friend because he didnt want his friend doing it. Well.... Ive been curious lately if hes done it. Hes been sketchy with his friends. This morning in his phone i saw messages of him talking to his friends about snorting it amd saying that they take it whenever its given.

We live eachother more than anything, but im so tired of the lies.

Idk what to do. I feel like I made a huge mistake moving my entire life to be with him.. Always cheating hiding, and worse lying about cocaine. My relationship hasnt been very baf, but in many ways it has been occasionaly verbally and mentally abusive. We have a 4 month old now, and i am 11 week pregnant with a second on the way.... I feel stuck, depressed, and disgusted that I love this man.

Im also a little worried to leave because ive tried doing it and he destroyed the suitcases and the house searching for mine and the babies passport.. He always tells me he wont let me leave him too.