of course you can live without her.
I know you don't want to, I didn't want to, but anyone who can live with an active alcoholic without actually combusting into purple flames will thrive and soar in the free world.
If you choose to stay, please don't make that choice out of a false fear of the alternative.
re ultimatum/boundary:
an ultimatum is a boundary - but it's the ultimate i.e. FINAL one.
definition (collins) :any final or peremptory demand, offer, or proposal
IMHO there is nothing wrong with an ultimatum, the problem comes when one issues repeated "ultimatums", because then they are just empty threats: just as "I will not live with" is an empty threat if we don't follow through....
the boundary is not the words we dress it up in - it's the action we take.