Complicated GREP style to bold a colon and escape a colon

[MadMac55]

Here is my challenge in a one-size-fits-all GREP style.   I am trying to write a grep style will make an exception for the colon in 7:30 but will bold all characters and including the colon in the “Today” example.

here is what I have tried   >>   ^[^?!:]+:      This does a good job forgetting any subsequent colons and trapping the first one in Bold.  However, it will bold all the characters including the colon in the first example.

So I then tried to combine the first part of the GREP with this >>  (\d:\d)   but that didn't do anything. 

The quick brown fox jumped over the lazy dog’s back at 7:30 pm. He was late for an appointment.

Today: Watch the quick brown fox jumped over the lazy dog’s back at 7:30 pm. He was late for an appointment.

Should I be exploring a Match?

Thanks, everyone.

[Kai Rübsamen · Accepted solution]

If I understand the goal correct, you want to find a colon, but not when the colon is followed by a number.

So try this one: ^[^?!:]+:(?!\d)

[MadMac55]

Kai, you are simply amazing.  Right under my nose.

I hope this benefits everyone in our community who finds themselves in a Catch 22.

thank you so much,

Chuck