Trying to conceive...I thought??

My husband and I have been trying to conceive since December. Each month im not pregnant is such a disappointment. I've told my husband that I feel like we aren't trying hard enough and not having sex as often as we should at specific times. He says that he doesn't like being scheduled for sex and wants it to be more spontaneous....ive tried wearing sexy things or doing it in places we don't normally do it but he still seems to not want to have sex as often as I think we should...im starting to feel like he just doesn't want to have another baby or hes not attracted to me anymore.