How about a night in? Do dinner - if you don't normally, then have a takeaway - make it different anyway. Open a bottle or two of wine, or beer, what ever takes your fancy and just relax infront of a video/dvd - if you have sky, try one of the sex titled progs - think they're on lateish. Let the wine take hold and relax.
I have the same probs from time to time... yes, and dh does too. I tend to have a glass or two of wine and take the mood - if I feel like kissing him, I will but differently - slowly and putting my arms around him, feeling his back.. whatever you feel like at the time.
Do you sit together or on separate chairs/sofas? If you sit apart, it can be a factor. Try sitting together.
IF you are both agreeable, try talking about it. Make a date to both sit down and discuss sex. There are many ways of getting back into the swing. Start by just reaching toward each other... not touching (Fully clothed). Take it a step at a time. You could end up killing yourselves laughing or ?????
Even if it doesn't happen on the night planned... don't worry. Best thing is to not really plan - unless you intend doing the step by step thing. It can release some of any inhibitions you both may have.
Good luck hun. There is always the other thing but gets thro batteries at an alarming rate.