Let's face it, pretty much everything in life comes down to relationship. Whether it's at home, in the workplace, online, or just in our heads, we have interactions with other people all the time.
Which means disagreements, of course.
Disagreement isn't bad per se (there's no learning, no growth without being wrong about stuff and having our beliefs challenged), but it can become problematic when it's habitual (posing as an insurmountable obstacle), or when it regularly escalates to hostility.