Is it hard to apologised? If you have too much of ego in your head, definately it will be hard.
I have today wrote an email to a vendor to clarify certain things, as I'm stucked in between the management and the vendor. In the course of doing so, the vendor some how got offended / uncomfortable or better still, the word he used "condescending tone". To avoid further complication, I just replied back my intension & apologised if he feel that way. It was never intended to be that way.
Sometimes, in certain situation, some one will have to be on softer side. If both are hard headed, until they will make situation worst.