[leaabc123]

Well, once TPR occurs, she is no longer the legal parent. Whether it happens voluntarily or not, is up to her.

I am assuming that you have had custody all of this time?

No one can say whether she will get better or not. That is entirely her choice.

I think you should be honest with her as to your feelings regarding who her parents will be. Also, you will need to set boundaries if visits will occur.

Some of these could be: Visits have to be set up ahead of time. Cancellations should be made within a timely manner.
Where visits will occur.
No strangers at visits.
Will visits ever be unsupervised.
What happens if mom shows up drunk or high for a visit?

If mom chooses no to get clean, it is perfectly reasonable to limit contact to photos and letters for a period of time. As the child gets older, you will need to explain things in an age appropriate manner. Kids are resiliant and understand more than we think.