Discouragement or Motivation: It's a Fine Line

I went to the doctor the other day, seems that I gained 7 of the 15 pounds I lost. Extremely discouraging. Under a lot of stress so I am trying to stay positive about it. But, other things went on yesterday that were discouraging as well. Things in my personal life. Motivation is everywhere I look but, dang it, I am too blind to see it. I feel like I never have enough time in the day. I go to bed at night thinking about all the ways I want to exercise the next day and I never do it. Why? Laziness? Fear of change? The pain I get from working out? And I don't just mean normal workout pain, because of my weight, my knees are starting to give, my right heel kills me every morning when I wake up, my plantar factitious sucks, and I hate, absolutely hate, feeling out of breath when I workout. But then I list all the things I hate about not working out... Being out of breath just getting out of bed, my knees hurting because of my weight, my heel hurting because of my weight, the difficulty I have getting up off the ground when I sit down to play with my son. It is EMBARRASSING!
You know, I started therapy not long ago and kind of discovered why I am the way I am. I mean, I've always been big, but it wasn't until something horrific happened to me that I just blew up. I am letting that one moment control my whole life and I had no idea. I am DONE being fat. I am DONE being out of breath. I am DONE hurting.