BF having friends snapchat

Okay so my BF and my friend has each others snapchat , they never snapchat each other but every time my boyfriend post something she always text me saying your going to let your BF do that or try to give me relationship advice that I never ask for. I always tell her I trust him but she stays in our business. I have told them both several times that I don't want them to have each other on snap chat but they both say I'm exeggerating . But I just don't like how she's in my business and always try to tell me what he's doing when I already know . I'm j just being extra or should I be upset ?