I'm a 38-year-old man. I'm ALWAYS in the mood. LOL To sweeten her up, I stay attentive to her wants. Always. I put coffee and her favorite yogurt on the night stand. I help with housework: dishes, laundry, etc. Weekly, I run silly errands. I bring her small gifts like chocolate and other treats every week.
She is particular about the kids not being home, if we are to be intimate. I understand that, so the only time we have is a two hour block on the day I get off early once a week. If she says, "No," during that one time per week then she has learned I don't FEEL like doing ANY of the aforementioned above.
For the most part, being consistent and patient has paid off well. Not to say I don't desire a whole lot more from her in that realm, but it is working for us right now.