Because maybe they were just having a bad day.

Because maybe they were sick and not feeling well, once they get better, they will apologize.

Because they have a mental illness and their meds got unaligned and once you take them to the doctor and get it straightened out they will go back to being their wonderful selves and will be shocked that they actually did this to you.

Because this is temporary, and after 20 years of being together, were they were a great partner, this is a new behavior and seems temporary.

Because there were years and years were they were not abusive, but were amazing and this may just be a temporary thing until they get better.

Because I said in sickness and health and I wanted to grow old with them and care for them and I'm being told that means putting up with their abuse.

Because they were there for me when I struggled and went through hard times, why can't I be there for them even though they are harming me?