Should the relationship be over when your boyfriend says he will never get engaged?
No. Nothing has changed in your relationship except that he doesn't want to get married, lots of couples don't get married and grow old together.
What does affective relationship means does affective relationship means boyfriend and girlfriend relationship?
No, interfering with a relationship will cause problems with their relationship and should never be something a person should do to another person and their relationship. You should wait for a while and see if she either breaks up with this person, or move on. You should not influence the relationship to break up, otherwise it'll cause problems.
if your boyfriend really loves you and cares about you,he should understand the concern you feel for him when he smokes pot,its understandable to be angry with him,but if he isn't pushing it on you or its not affecting your relationship,maybe you should let him carry on with his smoking,you never know he may get sick of it.