Ladies, I need to vent

lmk if I am overreacting!! so my boyfriend of 5 years has been acting super awful lately. Usually hes this sweet gentleman who opens doors for me and does the sweetest things for me! Thats the whole reason I started dating him was because no man has ever treated me so good. He treated me like a queen for 4 years then all of asudden he is the biggest douche of all time! He never has done drugs or anything like that (besides weed) but recently he has been going crazy about doing cocane and taking pills and things like that. Ive had an addictive past with all that type of things and he knows that I can only smoke weed because of that past. but hes been so pushy about getting pills and coke and all these other drugs that get you high right, he even went as far as taking morning glory seeds!!! like seriously what kind of shit is that taking seeds wtf. After i practically begged him to not take the pills/seeds he made me feel bad because i was ruining his fun. Hes also been cussing at me and arguing about everything. This is not the man i started dating and it kills me because he used to be so kind to me. I talked to him last night about it and he said he understood and that he wouldn't be rude to me anymore and that hes sorry blah blah ect. This morning as we were leaving for school and work this morning he was doing doing good then it was like somethinf snapped. He started yelling at me and being rude again. It ruined whole morning and now i feel so down and sad because he never acts like this. It just keeps getting worse. He snaps over the littlest things ever! idk what to do.