history: A colleague at my job took credit for months of my work and claimed I was of no help to them. It all worked out as it should have in the end, but that's never an easy situation. I recently was in a situation at work where I had a colleague take credit for months of my work_comma_ and go out of their way to tell my boss and others in a committee that I actually held the team back. Ugh I hate crap like that.  Why can't credit be shared?  Does it always have to be so cutthroat? Honestly_comma_ I'm indifferent as to how it's shared. Later_comma_ my boss actually sat me down and told me they knew my colleague was out of line. Ironically_comma_ their contract with our company was up two weeks later and they weren't renewed. 
current: Well All's well that ends well.  I'm sure glad they were able to see through such a cheap ploy.
next: It is what it is. I would never wish for anyone to lose their job, but I am thankful that in the end I was able to stay in the good graces of senior leadership.