I cannot contain my excitement. I had to re-read several lines, and each time, I feel the words pack an even stronger punch. Parts of this at first gave me a feeling of "The Giving Tree", but then, it turned darker. How you will use the parts of them remaining for resources, smartly using what is left, and perhaps doing so in a way to let them know you moved on. You lived THROUGH your nightmares. That's how I took it.
The last line legit gives me shivers! I took "fall" as a double entendre, as you wait for a new season but also the decaying of this person. The symbolism or metaphor of being a tree, and maybe providing you shade and comfort during the hot months, yet showing their true sides when the winds become cooler and more persistent, and they shirk away from their responsibilities. The painting their scars part also is fascinating to analyze. I see it as a way of empowerment, taking the parts of you that they imprinted on or changed, and giving it back to them. Or expressing all the ways you changed and grew and overcame because or in spite of them. That you still know who you are, and can differentiate between the parts of them in your life and your own wants/desires.
I absolutely adore how some parts of this remain undisclosed, like you don't have to reveal everything, and how that is open to the reader to take what they will from it. The imagery in this and your voice is probably the strongest I've read from you lately, in my opinion.
You take me by surprise every time, and this made me smile!!!
I dont want to comment on your interpretation whether its right, because I want to leave it with no explanation. Just one thing though the “fall” part is right, the double meaning is intentional :)