How to deal with a manipulative mother?

You don't have to be there for her, so why are you feeling any kind of obligation that you have to be? Just because she gave birth to you, doesn't mean that you are now in some way obligated for her care. She chose her drugs over you years ago, and now it sounds like her pain medication is taking the place of the heroin she was once addicted to, so really it's probably best for your mental health's sake, that you keep your distance. She has made her choices in life, and must now deal with the consequences, and you also get to make your own choices now in how you choose to proceed with her. Perhaps seeking some therapy for yourself, and learning how to set healthy boundaries would be a good place to start. I wish you the very best.

If she is abusing pain medication, then she's not a recovering addict.
Seek the advice and support of Nar-Anon. They will give you practical advice and strategies for dealing with your mom.
Good luck!

How do YOU and your siblings feel about this.

Did she LOSE her MOM badge by neglecting you all? She may have. Do you and your sibs have an open flow of conversation concerning perceived differences regarding the care she gave, OR DIDN’T GIVE you?

What do you as a group observe as “age related decline”? Does she actively want you to take care of her? Based on the fact that she gave birth to you? Are you all comfortable, or even willing to be participants in her care?

What kinds of “care” does she need? Does she expect financial support from you?

Is SHE in a step program or other addiction management type program? Are her “pain pills” LEGALLY administered by a medical doctor who is aware of her past?

Are you all in agreement when it comes to HOW TO DEAL with her?

Does “dealing with her” include refusing to participate in her “problem” and all of its related issues?

You are (wisely) acknowledging that she is “manipulative”, not a very positive attribute for recovery.

MY THOUGHT? Protect yourself, get to a narc anon meeting, work together as a sibling group. PROTECT YOURSELF. If your safety and your welfare depends on distance and detachment, do what YOU NEED to stay strong and healthy, and “help”, if you believe you can, from a distance.

Um. Well. There is what you are reasonably able to do, and then there is what she a) actually needs and b) appears to expect. Please note especially that her a) and b) do not necessarily have to be supplied by you; but could you say a little more about the mismatch between your willingness to provide and her a) + b)?

And who is included in the "us", please?