This is my best guess - try it at your own risk - something to think about: Xampp is usually used for development purposes, keeping it separate from your production is not a bad choice. Still, if you insist:
8 months ! Aren't you the patient one.
You could probably just configure a path to it, try this (always make backups before playing with files):
1. with Xampp running
2. find out which mysql is running by typing in which mysql in the terminal that will tell you which one your using. It should give you a path that should point to the Xampp version.
3. Next thing you want to do is point it to your regular mysql. By setting a path for it to look in
5.being extremely careful type this command: note the address has to be where your mysql bin file is located echo 'export PATH=$PATH:/usr/local/mysql/bin' >>~/.bash_profile
6. hit enter, nothing will appear to have happened but it did
7. now type in cat .bash_profile then enter
8. you should get the export path you previously typed in
9. quit out of Terminal
10. reopen Terminal and type which mysql and it should give you the address to you older version of mysql
As for your htdocs folder / change your php.ini file and point it to the htdocs folder your referring to.
8 months - wow