Hi old timer,

Whilst you could automate the insertion of a double space after every
period, you'd often find doing so inappropriate. For example, you probably
wouldn't want a double space after every abbreviation that ends with a
period, or following the last sentence in a paragraph.

Cheers

Better (and easier!) to break the habit.

Just a few references to encourage you --

http://www.elisad.org/gateway/Documents/styleguidance_typography.htm
No double-space after a dot, please. This is a bad habit!

http://www.mocabookdesign.com/more.html
Even today when many young people don't know what a typewriter is, the habit
of double spacing between sentences is widespread. The double space started
because a typewriter uses monospaced fonts. Each letter and punctuation mark
had exactly the same horizontal space assigned to it. The result was a
period that seemed to float between the last letter of a sentence and the
first letter of the next. The fix was to double space after the period.
Computers don't use monospaced fonts and printers never have. Periods now
sit comfortably close to the last letter in the sentence and there is no
need to double space. In fact the double space looks decidedly out of place.
Your designer should strip all the double spaces out of your text so if you
notice don't be surprised.

www.ideastraining.com/PDFs/TypographyBasics.pdf
Never double space after sentences and punctuation unless using mono-spaced
fonts. Typorgraphic fonts require only a single space after the period.

"In the 19th century, which was a dark and inflationary age in typography
and type design, many compositors were encouraged to stuff extra space
between sentences. Generations of twentieth-century typists were then taught
to do the same, by hitting the spacebar twice after every period. Your
typing as well as your typesetting will benefit from unlearning this quaint
Victorian habit." - Robert Bringhurst The Elements of Typographic Style