[Generally, he would love the chance for this sort of party, and appreciate the free food and drinks. But with the current gloomy situation elsewhere around the islands, and the fact that it's not showing any signs of getting better, he's finding it a little difficult to relax too much. It doesn't help that the nostalgic feeling in the air doesn't really make him feel any better, instead only getting homesick and wondering (as many probably did before during these weeks) if they'll finally be sent back for good.
So you can find him pacing around, heading outside to the gardens to walk through them for a while, then returning to the ballroom, and back again.]