Ya know.... I'm 54, and my h says very nice things to me and about my appearance. I think kinda like you.... I'm short, plain, a bit overweight.... but you wouldn't know it by the things he says. Until I met him, I dressed pretty conservative, like a mom and teacher.
I think his compliments feed my ego, and I appreciate him more....so I dress cuter for him, and the cycle continues. I just kinda think he loves me, and he must be half blind! He insists that its not so.
It took me awhile to accept his compliments. I'd laugh, or snicker at first....which wasn't a nice way to accept a compliment. I had to learn. I appreciate his words, and his desire...and he really appreciates my effort.
I dress sexier now, and sometimes downright trashy (but I have fun with it). I think it's mainly due to him, but also due to I'm older and I'll do what I want.
I pretty much have at least 3 wardrobes now. A teacher one, a sexyish date night/weekend one, the mom one w/ jeans and tshirts..... (oh, 4.....a biker wardrobe, just doesn't quite fit in those other categories!)
Anyway.... ya, you can be sexy to him! And ya, I think you have to make the effort to be attractive. He loves you, he will love the effort. Find your comfort level. I really pushed my comfort levels, and have a huge variety of "sexy" clothes that I do wear now. It doesn't have to be trampy....altho trampy can be fun, especially if you go out of town.... it can be a soft sheer top, snug jeans, having your toe nails done, wearing different earrings, an ankle bracelet? Whatever works. And you'll find out what works. Get your sister or bff to go and help you pick out one outfit. They will be honest and tell you what does not work. My sister tells me "Um, no." LOL
So instead of stressing, think compromise. Think positive and have fun with it.