Did you notice that you had changed before he said anything? I'm wondering if it is just the natural progression into being a long term couple, where you don't feel the immediate need for physical intimacy/affection. Plus, it sounds like you're pretty busy, and being pretty busy tends come with stress. Also, I'm wondering if you two simply have different ways of expressing love for the other, and in the beginning you were showing love in the way he understands, but now that you two are secure in your relationship, you're showing love the way you feel more comfortable, yet he doesn't understand? (Sorry, I'm reading the book, Things I Wish I Knew Before I got Married, by Gary Chapman, the same guy that wrote the book about love languages).

Another side note, I struggle with depression and I find, even when it's under control (either before by medications, or now without), I have these periods of time where I know I love my fiance, know it with all my heart and being, but at the same time, don't really feel it. It's hard to describe it, but when I mentioned it to my fiance, he understand (he was really depressed for awhile because of his previous job). Could something like this be happening?

Good luck, sending warm thoughts your direction!