Opinions of others

Staff 360 evaluation happening at work. I always struggle with this process.

Makes me uncomfortable to fill them out on my co-workers. I never say what I really want to say...A is transparent and a princess and self absorbed, B is lacking sincerity and is too cavalier and does not respect boundaries, C has  narrow life experience and makes his judgments poor D always pushes her responsibilities off on others to keep her job easy. I do not write down what I think. I put the filter on and diplomatically only focus on the positive on everyone. Why is that? Something in me is not approaching the process properly. I can actually feel that. There may be things in the process that are corrupt, but I am taking it personally .. maybe more than I should...I am not looking at the process objectively...maybe if I could look at the process objectively I might be able to see where my actual discomfort originates.
That acknowledgment is progress...Historically My first reaction is defensive...these people are not qualified to judge me...it was not a request that originated from me. I then I immediately dismiss them and their opinions. The coin flips and I tell myself This is a way to learn about yourself. Then I reject it. And then I tell myself others you respect,  respect this process. And so I go back and forth.