Strange as this may seem, when a couple increases the sexual frequency, it may increase the womens desire for sex whil actually causing the mans desire to decline! see the link How Frequency Effects Desire In Men and Women
Literally, practice make perfect for women. In theory, the more sex you have, the easier it will become to get aroused and be enjoyable, and the more you will desire sex. Toss in the fact that women have a greater capacity for sex, and your heading for nirvana. You need to find out how often your hubby wants sex, once week, twice a week, everyday, every third day, etc..
You are doing GREAT. Don't let down, you are being the PERFECT wife. You may actually find out that you really wanted sex more then you thought!