My Failing at Work

my boss handed me my 5 yr plaque and pin..
he said its has been a great 5 yrs.. and hopes the next 5 yrs are just as delightful..
later my coworker came in, shook my hand and chuckled.. he said he like it when my boss said that, cause he know how my attitude with the company has been the past year...
at first Ii thought.. that's funny.
then I realized how transparent I am at work with my dissatisfaction, so much so that an employee knows it..
my question is.. if I appear to be bitter and ungrateful for my job, then how are they to see Christ in me.. sure I can hold doors and say God Bless you.. but does not the bitterness mask the love and joy that God wants to show in me..
I have failed in this arena , because although I may be a God willed, God loving, loving person, I have let a hint of despair and sadness mask the true nature of God's work in us..

In the end, all the words I may speak about God and his greatness will only be written in my mind and heavy on my heart, the true things remembered are my actions and attitudes, and whether or not they reflect God