@littlegeenfinch,
Fly away, littlegreenfinch, fly as fast as you can to your lawyer and change that will back to what you had before, best done with your 'partner' in the lawyer's office.
NO marriage"partner" and from what you've stated here, I use the term 'partner' lightly, makes a partner, or any person for that matter, change THEIR will that describes how they want THEIR money distributed.
Again, only from what you've stated here, you should feel more than uncomfortable.