Feeling insecure about stretchmarks from pregnancy?

my son is 4 and a half months old now, and when i was pregnant i got stretch marks up and down my sides, all around my belly button and on my lower stomach. and i got that brown line down the middle of my belly, which is still there! but has faded a little, and i lost all the baby weight but my stomach is still kinda flabby...and about 2 weeks ago one of my friends had a baby and a little bit ago she posted pictures of her in the delivery room and a picture of her belly right before her baby was born...and she had ZERO stretchmarks! her belly was flawless it made me so envious, and now im feeling super insecure about my stretchmarks and flabby stomach and brown bellybutton. how can i embrace or at least accept what i cant change now.