I am in the same position as you. Before i found out about his drug use everything was amazing, he was an amazing stepdad to my kids.
Since finding out it has been a downward spiral of lies and deceit.
Hes horrible to be around. Hes been through very bad bouts of depression which he has now got meds for but only because i made him. He was paranoid and accused me of allsorts. Hes really hurt me along the way and broke my trust so many times.
He told me he would commit to therapy and only went 3 times and used to lie about going. He never gets up before 12-1pm. It was 4.45pm yesterday when he got up and me and the children had gone for a nice walk in the sun he was laid there all day. Which frustrates me so much.
I could easily just walk away from it all. Im always here to talk because i do understand where you are coming from. Its so difficult