I love my husband but what I don't want to have sex, but I want to keep him happy, what should I do?

I had the same feelings too. Just becos I'm too tired sometimes after a long day with kids & doesn't have sex drives towards him. But I didn't mean I no longer love him. I did honestly told him about it & he said it's ok if I'm tired. After awhile I think making love is the way to maintain happy relationships between us at least for him. Try making at different places or timing.