It's possible to transition.
I see where your mom is concerned. But you can be as healthy as the next person if you are conscience.
Maybe try substituting the meat products with products like:
Gardein,
Boca,
Morningstar Farm, etc.
You can work with a nutritionist, if your mom doesn't feel comfortable. Also, you get to stock up on the yummy beans, and legumes. Fruits and vegetables. Nuts, Granola, dried food stuffs. There's a lot of soy products out there. Almond milks, and so forth.
And, for me, my own personal transition helped free me from my own demons. For me, my own choice of becoming vegetarian, was a conscience one. I could feed my body good foods, and not feel that I was harming any other living being. Your reason is up to you. I'm just letting you know that it is possible to transition and be healthy.
Glad to have you.