how to deal with having no social life

im 19F and i literally have no friends, only few people whom i talk to when in college. i only have my bf(21M) as a friend. i can make friends im fun too but everytime i end being used as a backup option and when i realise im the one putting more efforts i take a step back because i feel being alone is better than this kind of friendship. i dont and have never had any friends to go chill out with have a laugh with, everytime i just get replaced. when my bf tells me about his plans to go out with his friends, i feel bad. not for him, not jealous because of him, i feel good for him that he has friedns and goes to hangout with them, but at the same time i get a reality check that i have no one to go hang with, i feel very emotional and sad for myself. i feel very heavy. he has friends to play video games with and to just go for a hangout and i have no one. he keeps going somewhere or the other and whenever he tells me about his plans i get reminded of my loneliness i feel so heavy and sad, but i try not to show it, i am happy for him but at the same time sad for myself how do i deal with this? how should I be happy happy for him and at the same time not feel so pathetic about myself for having no friends :(