Is this normal?

I love him. I like hanging out with him. There are more times than I care to admit that I feel like he could care less whether we're together or not. I know he loves me. He says he loves me. I feel the passion when we kiss or make love but other than that, there's not much there. I feel like I'm a nuisance and I just get in the way of his daily routine. I cook, clean, look pretty, am extremely conversational with his friends and family... I feel like I give and give and give but there isn't much in return. He constantly doubts our relationship and tells me about it often. He assures me that he wants to be with me but he has his doubts. Am I wasting my time? He's sweet, treats me right but I feel like I'm the only one trying in this relationship sometimes. Are relationships supposed to make you think/question them so often? I thought this was supposed to be easy and feel so natural. Sometimes it does... but lately it just doesn't. Maybe I should give it some more time? Maybe I should break up with him? Maybe we just need space from each other? Ugh! S.O.S.