How to far stretchmarks?

I know this isn't an awesome place to put this but A year of recovery from anorexia and the rapid amount of weight I put back on has made it so I have bright purple and red stretch marks all down my thighs to my calves. Please how do I get them to lighten at least. Things like this are the reason why it's made it so hard to recover and get to where I am now:((((