Jealously!?!?!?! please help?

im jealous of my best friend tht she gets her first kiss makes out and i nvr did all her friends did and i feel like left outt! how do i get ovr jealously?? pleasee helpo mee!!! i told my best friend and everythingg but idkk? please help mee!!! plus shes so skinnyyy and im a lil chubby! butughh it makes me so madd!