Social media dilemma
AD (nearly 13) is a keen user of Instagram Direct messaging, which in effect allows you to do the same as mobile phone texting (different from posting for all your followers to see). It's the way she stays in contact with friends from school - as it's a specialist school they all live scattered across the South West and AD can't meet up with them out of school. Just as with texting, it takes a single flick of a finger to delete these private message streams. I do some light touch monitoring of her messaging, which I've told her I'll do but she has clearly forgotten. If I made it part of our every day, AD would simply delete all her messages after sending. My main concern is to ensure that she doesn't get into deep trouble, e.g. being groomed or sexually explicit messaging, and I don't want to ban Instagram as she wouldn't be able to keep in contact with her friends. I also want her to learn to use social media sensibly, and not hide her use from me. AD doesn't have a smart phone, but has access to an iPad at home (for downstairs use only).
For the most part, her messaging is absolutely fine, but she occasionally uses awful language when she's annoyed about something one of her 'friends' has used - complaining in graphic terms to another friend (e.g. xx is a f**k*** b***h). I do occasionally remain her in general terms never to use such language about another person/swear in anger, and clearly I need to have another such conversation with her. In the past I have, e.g., banned her favourite films (Pitch Perfect) in which there is bad language, when she is going through a swearing phase.
Nothing has really worked so far. Any thoughts on how to help her move on from using such dreadful language particularly about other people?