Some might say you have Post Wedding Depression (I kid you not), all the fun build up to the wedding and holiday then back down to reality.
Now you've made sex an elephant in the room you need to address it by talking, and honestly saying how you expect your sex life to be.
We have runs of very regular sex then it might be 2 or 3 weeks before we do it again, and as Ummmm says, when there are kids in the house it can be difficult. My kids go to bed later than us at the weekend so that puts a spanner in the works.
Get the little one looked after, go out for a nice evening and talk to your wife about how you feel, she'll probably be relieved.
Good luck.