People can become homeless for any number of reasons, sometimes, mental illness is involved, but that is not stated in this case. Her rent was raised, and she could no longer pay the increased rent. It's likely, that due to her inability to pay her rent, she ruined her credit. <--this can be a big step down in one's ability to qualify to move somewhere else.
She also had debt. It can be difficult for someone with bad credit to find places to rent, as evicting a person is a landlord's nightmare, takes months, and during that time, the landlord is losing income and spending money to accomplish the eviction. This makes many landlords and property managers very leery to rent to those with no job, bad credit and debt and very low income.
Usually, the new tenant has to have first, last, deposit, as well as deposits for each and eveyr utility, and these deposits are usually higher
for those with bad credit or no job.
That can add up to $1000s of dollars to shell out, all at once, just to move in, and that could be impossible for an unemployed older person to do. Besides the higher deposits req'd of the poor----many property managers also require a "risk fee" (non-refundable!) to rent to anyone with no job, bad credit, debt, etc.
Many types of aide require the person has an address to receive it, as well as transportation to the building to apply for it, as well as knowledge this option even exists.
Older people are often the first to be let go when a company is downsizing. Older people tend to cost a company more to keep on, as their mere presence can raise the insurance rates for the company---the older person's chance of needing medical care is higher than the younger employee.
If the older person has been employee for a long time, they might be being paid more, and getting more vacation time, and they can be seen as 'too expensive' to keep on in hard times.
Older people today may have zero retirement funds, and many who did, lost their 401K in various stockmarket plunges. Some older people retirement pay disappeared when the company went under.---IF they had a job that even offered that at all.
The cost of healthcare is often a huge portion of an older person's monthly expenditures, far more than their rent.
Older people are more vulnerable to scams, as well, and some are taken advantage of in that way, too.
It's really not that shocking to ME anyway, that an older person can end up homeless, but, it makes it no less sad.