You don't know unless someone tells you. You don't know if it's ankle deep, knee deep, or even waist deep until you're up to neck deep.
When it's you in the relationship, it's very difficult to be observant of yourself.
When it's come to be obvious...it's been that bad for such a long time.
Some people don't put up with anything, zero tolerance. Some people have lots of patience or tolerance. Some people are always short fused, blowing up over nothing. Other's don't do anything until you light a fire under their butts. Then again sometimes that's useless because they only react and not the right way.