Starting a new Job

I have Left Sword & Shield to take a better opportunity with Coalfire Systems.
There were multiple reasons for leaving Sword & Shield, and most of them are related to one individual that has moved up the ranks in the company. He was originally hired to do report reviews five years back, and is now the Senior VP of services. Since his move into management there has been a drastic exodus of highly qualified personnel from the company. One major issue is that the CEO/President, Executive VP and COO do not even notice the main reason for the high personnel turnover.
Since I turned in my notice, the CEO and COO have completely ignored me. Walking down the hallway, I always say hello to everyone, and usually get a hello back from whomever is there. Not lately; had multiple encounters with the C suite and they literally walk past me as if I was not there.
I wish all my former colleagues well in there endeavors and hope things get better.