It's probably a sign of a relationship coming to an end, just through the attrition of time and familiarity, when a colleague greeted me this morning with a smile and a cheery
"Good morning! Hope you had a good weekend, happy new year to you!"
And all I could think of saying in reply was:
"Oh, go fuck yourself."
Time to leave, before I actually start saying these things out loud, rather than typing them up here in furious bursts of outrageously unreasonable and inappropriately disgruntled behaviour.