So many of us have been in your shoes so many times.
and it's time to start getting motivated..
So to avoid making the same mistake over and over again, I'd much prefer you get committed instead of motivated. Motivation is great, but it's not lasting. It's never around with the beer and pizza are - but that commitment - much more lasting.
When you commit to doing this no matter what, no matter what, no matter what, that's when you'll be able to say no to the drinking and all that other stuff. That's when you'll say yes to weighing daily, counting calories, exercise and all the good stuff.
Decide to do this, once and for all, no matter what and permanently. Decide to do this, commit to doing this and then go out there and get it done. No stopping. Just continuing. If a slip up should occur, you pick yourself right back up..right.back.up... no waiting for tomorrow or Monday.. but immediately (if not sooner).. Make any slip up that should occur a solo, singular event. All is not shot, all is not lost. Right back to it.
You CAN do this. You've got the ability to do it. And like you said it makes you happy. This is nothing to fear and loathe. Get back in the game.
I look forward to hearing of your progress.