sister, you need to fucking stop

My sister is the type of girl who can't be single. Once a boyfriend stops showering her with attention, she moves on to the next one. But she's also the type of girl who thinks she's in love with every one of her boyfriends. My family is very close. We did everything together. Holidays, birthdays, vacations you name it. My sister is always bringing a new guy around, tells us she loves him and that we should treat him like family. That's been 4 guys already that's joined the family. Well again, she has a new guy. We all told her we're not interested in getting to know him. We all know she's going to get bored soon and find someone new and shiny. She's swearing up and down she loves him but she's said that with all of them. She's pushing this guy on us and it's getting really annoying. We all got attached to her ex and we were all hoping that he'd be the guy she married. Now we're not even allowed to say his name. She used to lash out on me and my mom about this boyfriend. Used to call me a bitch and to go fuck myself because they were going to be together forever. Fast forward 3 months and they break up. I told her I don't care who she dates. She can date whomever the hell she wants but to stop making every dude she dates a new member of our family. We're ALL sick of it. She's trying to invite him to my son's first birthday party and I told her no. She's trying to include him in on our family holiday this summer and we said no. She thinks we're being cruel when really we don't want to like another guy and then have to meet another one in a few months. I love my sister but she changes boyfriends more than she does her underwear and she talks to guys on the side while having a boyfriend. She's saying we're ridiculous but we've just grown tired of having different guys around. 🤷🏻🤷🏻