Text Editor which shows \r\n?

With Notepad++, you can show end-of-line characters. It shows CR and LF, instead of "\r" and "\n", but it gets the point across. However, it will still insert the line breaks. But you do get to see the line-ending characters.

To use Notepad++ for this, open the View menu, open the Show Symbols slide out, and select either "Show all characters" or "Show end-of-line characters".

In vi(m), check out:

:help 'list'
:help 'listchars'