how old is too old to live in a house share?

Lots of people separate or divorce in their 30's/40's/50's.
If you're the main breadwinner you might be having to pay for the mortgage/rent/running costs of the home you left so have no choice but to house-share.

Dude I'm in my 50s and I've lived in squats and flophouses

Many of us are now forced to share a living space with others. Rents are obscene and out of control...greed...homes are often priced in the millions now...out of reach for most of us. Unless we want to be up to our hairline in debt...sharing is the best way to survive financially. It sucks

It's not a matter of how old you are you see. It a matter of what your financial condition allows you to afford and whether takes interferes with your mission to spread the word of Christ

There's no right or wrong answer.
It's a personal decision.
Sounds like you want your own space.
Cool!
Go get it.