Well, it's a complex problem. You might want to try to keep your distance politely from her mother while making sure not to cause any major conflicts within the relationship. And definitely communicate openly with your girlfriend throughout the process.
If a boy is in such an unexpected situation, he should immediately remove himself from the situation to avoid further harm. Then, he should talk to his girlfriend about it and explain how inappropriate and uncomfortable it made him feel. It's important that they communicate and decide together how to handle this odd and unacceptable behavior from her mother.
Well, first of all, don't jump to conclusions. Maybe start by observing her daily routine more closely. Notice if she's acting differently around you or if she seems to be avoiding certain topics. Another thing you could do is try to spend more time with her and see if she's receptive or if she tries to avoid being alone with you. If things still seem off, then it might be time for a serious talk.
Harry might consider writing down all his observations and experiences in detail to present a more compelling case. Also, he could look for secret or forgotten magical spells or items that could prove his claims.
He should probably stay calm at first. Reacting angrily or aggressively would only make the situation worse. He could say something like 'I'm sorry for whatever I did wrong, but this is not an appropriate way to handle it' in a very respectful tone.
You should stay away. Having feelings for your best friend's girlfriend is a tricky situation. Acting on those feelings could damage your friendship and cause a lot of pain for all involved.
If it's a situation where you are an observer, it's important to first ensure the well - being of all parties involved. You may need to encourage communication to address the issue in a calm and respectful way. But if it's something that makes you uncomfortable or goes against your values, you can distance yourself from the situation.
The person who hears this should stop the wife immediately and remind her that it is inappropriate. Then, if possible, try to protect the privacy of the girlfriend by not spreading the story further.
Apologize immediately and then remove themselves from the situation as quickly as possible.
First, you should turn away at once and then sincerely apologize. After that, try to keep this incident private and not spread it around. It's crucial to respect her privacy and dignity, and not make the situation more embarrassing or uncomfortable for her.
The son would probably feel extremely embarrassed. He could simply ask his mother to leave the room immediately and then later try to put it out of his mind. He might also want to have a conversation with his mother about the importance of privacy in general, without getting too specific about the incident.