Smile and be positive. If there are parts of the story that are exciting or happy, let your emotions show. It will make them feel that you are enjoying sharing this moment with them. Also, don't be judgmental. Everyone has different experiences, and they are choosing to share this with you, so accept it gracefully.
I don't think it's appropriate or respectful to discuss such a topic. It involves personal and potentially sensitive matters that should be dealt with privately and respectfully.
You could also search on social media groups dedicated to cat lovers. People often share their own experiences and stories about their cats there. For example, on Facebook, there are numerous cat - lover groups where you can find a wealth of cat - related tales.
This is a very difficult and disturbing situation. You must act quickly and assertively. Start by having a private talk with your mother. Express your extreme discomfort and make it clear that this behavior is unacceptable. At the same time, be there for your girlfriend. Listen to her feelings and offer her all the support she needs. You may also need to consider involving a professional counselor if the situation is too complex to handle on your own.
Tell her how sorry you are right away. Listen to her feelings without interrupting. Maybe offer to do all her chores for a week or something like that. Also, show her that you trust her by giving her more access to your own private things. It'll take time to make it up, but being sincere is key.
You should firmly but politely tell her that such behavior is inappropriate. For example, you could say, 'I'm not comfortable with you slapping my ass. Please respect my personal boundaries.'
You can start by listening to her. Really listen when she talks about her day, her dreams, or her problems. Women often feel loved when they are heard. Also, small surprises like bringing her favorite flowers or a book she has been wanting to read can brighten her day.