HELP, my relationship's about to end...?

I have been with my partner for 4 years and i love him to death.......but......about two years ago he started smoking dope morning noon and night......he lost his job......has been on antidepressants for 6 months , has been seeing a phsycologist for his mood swings and just lost his zest for life. He only talks to me when he needs money (we live together so one wage is hard). our life is non existent and i feel that he is not physycally interested in me although i cant go anywhere without him drilling me with questions as to where i have been and who i was with. the paranoia is killing me. if i get a text msg he needs to see it, and if the phone rings he follows me around the house to listen in, i have told him that he needs to quit if he wants the relationship to survive.......how long do i have to wait??? HELP