Mixed Feelings When I Need To Be Happy For Her... HELP QUICK!

This morning my wife unofficially found out that she's getting a rather big promotion, with a commensurate pay raise!

I am super-happy for her, and ultra-proud of her!  This is something she's been working really hard for and it's finally paid off!  The extra money would take the strain off our finances, and would relieve a lot of stress that's been building up in the family over it.  However...

In the back of my mind, that nasty little voice is reminding me that it also means she wouldn't have to worry so much about money if she decided to move out immediately.  It's ruining everything.

QUICK!  Help me shut that voice up, so I can be as happy for her about this as I really want to be...  I've got about half an hour before I get home!  HELP!