Hi there! We are kind of in the same boat. I'm a little older and have one less child, but our goals are about the same and I feel the same (about being the fat friend, etc.)
I'm down 15 pounds and have a ways to go. What I've done so far is take it day by day and I am really thinking about what I'm putting in to my mouth.
I really don't want to walk around the neighborhood (because I've been here 12 years and people have seen me balloon up and I cringe at even thinking about it), so I've been trying to hit the treadmill as soon as I come home from taking the kids to school. I don't set a time, just get on the thing and go. Getting on the the treadmill seems to be my obstacle. When I get on, I'm fine. I just do whatever I can do. Put the music on and go.
We still have a few months to go and I'm confident my small changes will get me somewhere. My goal is to be a good deal down from where I was last summer. I will not let myself be disappointed if I'm in the 150s or 160s. It will be a huge improvement. This is my first approach to living this way, and so far so good.
Good luck to you. You can do this, one day at a time.

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