I'm sorry your mom is such a drainer. That's frustrating. I hate that catty BS. I know you said she was abused, but so many people are abused. You can either learn to heal or just let it rule your life. I guess she chose to let it rule her.

It's not a hard meditation. But, you can accidentally cut off people you don't mean to. Which is why, it is usually guided and you appeal to a higher power whatever that may be. Such as a spirit guide. Or a diety (which you said you are not prone to diety, which is fine.) I know there are some hier power type principles in yoga, although I don't know them right off my head... Even like animal guides or angels, whatever rings most true to you, that's the key here. My spirit guide was a little old lady with long black hair. She was wearing a dress made out of the images of animals that shifted. It's been a long time, over 8 years, but I still see her pretty clearly.

But, anyway, you just go down into a safe space, and your spirit guide will come to you when you call. You ask the spirit guide to assist you with your cords. I think if you don't actually want to cut them, you can ask to do other things. Maybe tie a knot in it, so the energy can't flow freely? You can also ask to have the ones removed that you no longer need. Such as all of those random people at the store who walk up and start asking you "have you tried this brownie mix" or "can you reach that on the top shelf for me?" You know, those things.... Your spirit guide can do the cutting for you, if you prefer.

You being in yoga, I guess you already have a safe meditation space (like not meaning physical,) but if you don't let me know.