Might not just be the puppy, though that is the most "obvious" change in your life. One year is a huge milestone. For some it's like, "okay, will I do this forever now?" others it is wow, made it a year and then "thoughts" start creeping in. With all the energy you put towards making that one year mark and then made, it's like, "ok, what's left now"............then its anxiety. Not saying the puppy is not a handful and stressful as we have 3 dogs of differing variety. A year is a huge accomplishment. Congratulations. Create some goals and enjoy a sober life.