Fear after I lose weight

I have a lot of fear about how I will look after I lose weight. I have a significant amount of weight to lose (120lbs) and I’m afraid that I will look old, have thin, stringy hair, lots of loose skin, very little muscle, just generally not very attractive.

I’m desperately unhappy with how I look now but I am equally scared of what I will look like 120lbs lighter.

How can I start to process this so my weight loss sticks?

In the past, I have lost 40lbs very easily and very joyfully. But it didn’t last and I gained 50 back. I’m really of afraid of not being able to maintain my loss and hating how I look when I get there.