every guy i talk to my best friend steals

i will start talking to a guy and she will automatically add him on snapchat and instagram. she says it’s for ‘stalking them to see if they’re right for me’ but she ends up taking to them AND sleeping with them and then telling me all about it. i don’t know if she knows she’s doing this but it’s making me really pissed off and annoyed. also kinda sad because they always choose her. idk. i’ve always felt like i’m not enough with my parents and now i feel like i am not enough for these guys. am i overreacting? she’s done this with the past six guys i’ve talked to and she is now onto the seventh.