My boyfriend is not interested in sex

I have been dating with me boyfriend for almost 2year's and he is my first boyfriend. We have been staying together and most on the time we will be together. My boyfriend is very Nice guy, he is 24 year's old and I'm will turn 21. We have normal relationship like other couple but in term of intame or sex I only get once a month or once after two month. He will say that he is tired or maybe not in the mood to doing it. I am lucky to have sex one every month or two. For him I'm so abnormal because I'm really in to having sex. Is it bad to have that feeling to make out with your partner? To look into his eye and think how sexy he is?We have a wonderful relationship besides this, but it hurts so bad because he doesn't want me the way I want him.I've tried dressing sexy,offering sexual favors to get him in the mood & flirting, etc But nothing change. I really feel ashamed of my self, frustrated and felling down most of the time. I don't know whether something wrong with me or with my body.My boyfriend is addicted with pornographic. I realize it when he like to be a wake at night. I ask him to stop doing it because for me this is not normal But not for him. My boyfriend prefer to masturbate while watching porn rather then doing it with me. He say it not tired at all and sometimes it fun to doing it. What I should do with it.I work hard to make our relationship to be normal and I don't see the end of what am I doing right now. I do love him but I have needs too. Sex is not all I care about but most people want that in their relationship. I don't want to end our relationship or cheating on him. But I don't know until when I still can smile and try to make it right. Please help me... I really need to have some advice on this relationship.