The speaker is referring to the fact that lovers can get easily addicted to each others.Not necessary sexually but many times they are also addicte to the lovers voice, aura or just their presence. People who are addicted do feel a need to get the object of their addiction, In this cast the beloved one is the object of the addiction. People refer many times to their addition to the beloved one saying: "I miss you" and"I cannot live witrhout you" . Love is one of the best addictions on earth. I am convinced that people should not need drugs when they should really love someone.

sorry but this is the ultimate truth: I love you because I need you: is always said by a horny guy trying to fool a girl in love with him!!! I need you because I love: is always honstly said by me (the angel) because I'm the best guy a girl can get!!!

It depends on the speaker's thinking . In my opinion , the speaker seems to need you in all his life because he loves you . But It's just my expectation and you should ask him again in order to avoid the misunderstanding !