Your post is one of those that I will remember. The question of moral decay seems to be at the heart of so many conversations about the confusing nature of relationships that have become destructively out of balance in a family. Many times it seemed like some kind of moral decay had to be behind the life my parents created for the family they were raising. In the end, it was simply a choice they made. For my own reasons, I am not making those choices today.
One of my big regrets is that my standards had to be lowered when they didn't need to. Because I could not face what had actually happened, I assumed that some moral decay was necessary in life and this led me into getting involved with kinds of people who ultimately I could not respect. It has taken me a long time to see where I picked up the attitudes that led me to do this.
Your questioning here about the moral nature of a relationship to oneself and others seems to be a form of self-love. To ask the question of what standards you want to live by is a way to feel and understand yourself.
When misperceptions build up between two people, they can in their own way constitute a lie. When we feel misunderstood and unable to show who we truly are, it can seem impossible to rid oneself of the habitual experience of feeling like life is a lie around a certain person. And when that person is our mother, it can seem not only impossible but wrong to try and undo the lie.
In order to make relationships clear by improving boundaries, lying is sometimes necessary. This may be because boundaries have been crossed for so long that the feeling of living the lie is ingrained. With new space within a relationship, it can become possible to perceive the pattern of how things got messed up in the first place. This is very valuable information. It may help reveal unconscious dynamics that led to the chronic forms of abuse that you have described. In this way, choosing to lie with the intention of undoing bigger lies seems like a stronger moral choice.
I have had to make this choice with both parents at times. When things improved later on, I was able to slowly establish greater trust and let the smaller lies fade into the past. Integrity is ultimately cultivated by you and only you, not by a parent who attempts to convince you that you are someone only they want to see.
Although financial help can seem like an invitation to revert to old patterns, this may not necessarily be true. My mother (and perp) has been willing to pay for some of my therapy. Although we haven't explicitly talked about the connection of my pain to any mistakes on her part, the journey to some kind of healing for both of us has been understood.
Best of luck with your visit and your new direction.
Lose the drama; life is a poem.