I Planned Only So Far

I lost all the weight I planned for with the SO program.
Since I chose a protocol that I could live with for the rest of my life, I just kept eating that but at a certain point I did not want to continue losing more weight.

I started at 187 and reached 125 and felt great. When I reached 120 I felt too thin, and did not like that look.
I think that since I struggled with losing weight for so many years I did not plan for the maintenance phase, only for the weight loss phase.

What do you suggest doing to stop further weight loss when we are trying to stay on the protocol we chose for ourselves?