Taking things personally is not a bad thing, it actually helps you succeed in life.
The thing that makes you take things personally, is EGO! Ego is also not always a bad thing, it is what makes you want to be number one, it brings pride in your work, it makes you work harder to deliver good product and be a good leader and what not!
But, the problem comes when ego actually prevents you from listening to the critiques that you are being told. That is a bad way taking things personally.
For instance, I got some critique on the other day. I got somebody sent me a message and they said that I did not explain something well enough, as I did not explain what a word, I used in my article, meant!
My first reaction to this was, well if you do not know what that word means, google it! That was my ego saying:
Hey I cannot believe this person is asking me about that, and critiquing me for the way I write my articles!
Then, I remembered a saying I once heard:
The angrier you are, and the more personally you take the criticism, the truer it actually is!