Pictures don't lie, and I don't like the truth

I love my boys, and they are one of my main motivations to loose weight. 
Yesterday, we were playing on the couch.  They were taking my glasses and hat and putting them on - it was a really nice moment where we were laughing and playing, and my husband took some pictures on his iPhone. Whoa - I look 300 lbs!  Granted, we just came back from a 2.5 mile walk, but I really couldn't believe how I looked.  I will consider these pictures "before" pics. 
My motivation feels different this time - I feel more determined. 
I always considered anything below 253.8 to be there just for a visit, but not to stay.  Every time I try to loose, I do great until I get to 253.8, and I just can't get below that. 
I feel like weight loss is an elastic band, and the more I loose, the tighter the band gets - just waiting to snap back to my starting weight.  Once it gets to 253.8, that's it max and it will snap back.
I really hope it's different this time.  I'm fed up with this weight.  I'm more motivated than ever.