I'm very much like this and it takes a lot of effort for me to question my black and white thinking. It can be helpful to acknowledge when you are more inclined to think 'grey', to try and apply that perception to other things. For example, I am able to see other peoples' relationships as complex and do not see them as either perfect or terrible (whereas my own relationships often seem this way to me).
To be honest DBT has been really helpful.
This book is really good, and updated from the classic manuals. It includes more skills around middle ground thinking and explanation of dialectics. I would really recommend it if you are looking to make active changes to how you feel at the moment.