IF she qualified for disability in Ontario & I'm pretty sure it's not the obesity per se but a complication of it she'd have to work with her doctor; she's going to have to jump some stiff hurdles to get on it. And even if she does, she's screwed. It pays $1,075 per month total, no matter where you live in the province & Ottawa isn't cheap. That's right, that's all she'd get. Period. End of discussion. As a low income person, she'd also get a bit north of $50 per month rebate of provincial sales tax & a federal check once a year for roughly $300-350 for rebate of federal sales tax.
She'd have to try & find a place to live & in Ottawa, even a single room is going to take most of her monthly check. She can kiss the car good-bye as well as her cell phone & internet; we pay through the nose for that here. If she was really lucky, she'd be left with maybe $200 per month for food, clothing, toiletries, OTC meds; they're not covered. Sure she can always use food banks but most limit you to 1 box per month & it's not the type of food our Dainty Miss enjoys.
Welfare? Current rates of payment would give her maybe 50-60% of what she'd get on disability. Unless she could fall back on her family, she'd be utterly screwed.
Working? Recently someone mentioned a job in her comment section; something about working a real job with like - hours & such & her response, iirc was: "Ew!". So yeah, that's not happening. She wouldn't last more than a few days at a call center. They're tough to work for at the best of times & I doubt they're short of personable applicants right now.