[Rivière]

Have you discussed any of this with your mum? If you haven't, it may be a good idea to. She needs to know how much her behaviour is suffocating you and will eventually affect your mental wellbeing, if it hasn't started/isn't already.

With all of that said, it would definitely be worth looking into why your mum is behaving like this. Based on what you've said, you're quite literally all she has. She has no friends, your father doesn't have anything to do with you/her, your sister has started to ignore her. It must be a terribly lonely life for her and you're the one thing she's clinging on to to help push away the loneliness. I think she needs to be made aware of her behaviour, and perhaps encourage her to go into the world and meet other people. Possibly even get her to go out to a local pub (not necessarily to drink) and take part in some of the events to meet people. Or possibly get her more involved with any sorts of hobbies she enjoys. This will put her in a better position to branch out and meet new people.

All in all, talk to your mum. Make sure she's fully aware of the effect she's having on you. You're 22. You can't live at home forever. You're going to have to leave home at some point and whether she likes it or not, you're going to end up going away and making a family of your own. You can't do that if you're stuck at home with a clingy, suffocating parent.