Hopefully my punny title hasn't put anyone off.
I am taking a series of courses to become a certified financial planner, the current course I am taking is on Estate Planning, and last night's topic was 'estate planning for non-traditional couples'.
I didn't make the law, so don't shoot the messenger, but the bottom line is that marriage confers significant rights that are not available to everyone. HOWEVER, you can protect your interests (to a large degree) by planning your estate in a legally binding manner.
So, if you want the person you've been living with for 10 years making decisions for you if you're medically incapacitated (and not your legal next of kin Aunt Mildred who never really approved) then you need to get some legal documents prepared.
If you want your assets to pass to the person you love, you need to get some legal documents prepared. And find a lawyer who specializes in this type of thing - wills CAN be challenged, you want yours to be bullet proof in court.
Seriously - do not let your loved one find out in the hallway of a hospital that in addition to being emotionally devastated half the house just passed to your brother who is still using. Take care of yourselves.