My friends lost their virginity?

they're 16 and lost their virginity to their 21 year old boyfriends who they fight with or get mad at all the time. is it just me or are they really stupid? they could end up pregnant; they still do it. their parents would KILL them. and honestly, i think their boyfriends are complete ******* and they're just using my friends. i hope they break up and regret everything they did because i'm so tired of worrying about them all the time. is that wrong of me? they're always talking/calling/texting me about a fight they had, how they might be pregnant 'cause some of their pregnancy tests came out positive, how they cried for hours over something their boyfriend did. i am so sick of this... i'm so worried. i don't know what to do. i tell them things over and over and over again but they never listen; they go and do what they please.. it's like i'm nothing to them anymore and they don't even care about what i say. all they care about are their no good jerky d-bag player boyfriends and keeping them satisfied. what is this?! we'd make plans to hang out and then all of a sudden they can't because their boyfriend decided to take them shopping or something. or they invite me to see a movie but then ditch me and go see it with their boyfriend because they're off from work or whatever. UGGGHHHH. it hurts.. what should i do..