Advice please

is me getting mad justified if some girl sent a snap to my boyfriend wearing a bikini top with half her boobs out? (that girl is his good friend and also the girlfriend of his bsf and also the girl's boyfriend i.e. my boyfriend's bestfriend, got mad at her for sending that snap to everyone including my bf

getting mad at my bf***

Another reason why guys shouldn't have girls as good friends if they're dating...you don't have any reason to be angry really cause you allowed it to happen.

You/re mad at your BF for receiving a message he didn't ask for?

yeah cause I'm jealous that he's seen it and still keeps snapping her and talking to her

well that tells you all you need to know. Your bf doesn't seem to have a problem with it as you have allowed him to be good friends with her.
Honestly I don't get why you have a reason to be mad when you shouldn't even have allowed your bf to be having a close friend that is a girl as how can this kind of thing not happen, are you living in dreamland?