whats the cure for jealousy

i get jealous at seeing other people laughing, happy and enjoying life, because my adult life has been very difficult, mainly dealing with mental health issues and i missed out on a lot....so when i see people happy, smiling , laughing etc, it reminds me of what i always wanted but never got..............my childhood was wonderful, just my adulthood which was mega hard....and i feel jealous and bitter a lot and push people away.

i'm almost 47 now.

what do you say?