That's more like a sore loser, you can't be "mentally weak" and put the act Colby has been doing for all these years, a real mentally weak fighter would have already crumble like Honda specially after his fellow friends turned their back on him (rightfully so)
He have one of the strongest will in the sport, just his style alone should be a clear indicator and after his lost to Fakenewsman he returned as focused as ever and put a beat down and finished Woodley.
And lets not forget Marty faked a low blow, not trying to justifying Colby in that part but I guess he is doing what he can to get that rematch regardless if it will work or not