@Zow
So, couple questions/observations
1) Common story. I was there to some degree. It's easy to allow it to happen. But once it does, it's a lifestyle. It's not a lack of time, even though time is a precious commodity and you may have less free time than you were used to when single and 27 years old. That said, eating habits don't take that much additional time. It's a matter of making the lifestyle change back for the better. If you look hard at it, it's just an excuse for not wanting to commit to that change. Most of the weight gain (and subsequent weight loss) are diet related. The exercise is there for further health and should be included. But at least address the major part of the weight problem.
2) Would you care if your wife put on 60 pounds after you married her? Does she care that you have? That would be an issue for some and not an illegitimate concern either.
3) I posed this question to Otis already. Do you want to be around for your grandkids? Do you want to be able to be active with them. Carrying an additional 60 pounds is going to limit both of those if it continues long term. If you don't want to do it for yourself, do it for them. Not to mention modeling the behavior of taking care of yourself that you can pass on.
The bet is all well and good, but it should only be viewed as a jumping off point. Use it to see changes early on but decide now that it's going to be your last weight loss bet because you won't need one in the future.
Mind you, I'm not some crazy skinny health nut. Far from it. But I've prioritized taking care of myself over the last few years and won't let that change again as long as I have any control over it.
Good luck.