She IS providing for him. She is, whether she's in a shelter or couch-surfing, providing a roof over his head, food in his belly, the whole nine years.
You are no longer on an even footing with Mom. Now you need to prove that she's either unfit (she's not, by the legal standard), or that there has been a significant change in the child's circumstance.
If you DO have a CoC, you'll then need to show that switching custody is in the child's best interest.