Well, to be fair Luke has only been functional for about a month. And they do share a house with 11 (12 now that apparently Lily has moved in too) other people. Also, I think Luke is way more nervous and intimidated by the idea of getting physical then he lets on. It's not completely unbelievable from my perspective, but they are starting to push it.

I think it's gonna happen soon. They've got a new storyline coming up and I think it's definitely gonna happen before then.