Wow... your mom has dodged a bullet and next time might not be so lucky. She has been given a chance or a wake up call. It's easy to say she needs to change her ways and needs to lose weight, but it needs to be controlled and something she can handle. You don't want drastic changes as then it seems to hard.
If you are going to share a plan with your mom, that's great, you can encourage and praise each other.
You need to work out what foods you eat now and what need to be replaced. Sounds like sugars and fats are something your mom needs to address, so reducing carbs and more protein could be something you look at. Carbs turn to sugar if you don't burn them off, which is where hypertension comes in and to fix the high cholesterol she should look at lean meats for protein.
Best wishes to you and your mom, we are here for both of you