Takes awhile to get acclimated to the free time. To me it felt like I finally quit my second job. I picked weight training / weight loss as a yearlong goal to focus on, so far I've been 85% diligent in sticking to that goal, and 85% is plenty enough to get some things accomplished.
The one year mark is rolling around in the end of June, and I'm getting pretty close to where I want to be on weight/physique, so starting to think about a new goal for this year. Considering really locking-in on getting my jazz guitar skills up to date. Also wanted to get to marathon shape over the next year or so, run the local city marathon next year, so that is another thing I'm contemplating. Oh, and maybe start dating again. That seems like a lot of work though ..
So enough of my anecdotes already! In short, you might pick a long-term goal you've always wanted to accomplish but never took up because drinking either took up too much of your time, or made you too unreliable to commit to long-term goals. That kind of thing tends to fill your free time. Or go get an accounting degree (oh what fun it is to actuary. . ) or other career improvement stuffs.