Don't use sweets, coffee. This will help to stabilize mind.
You should start meditating every day for 15 mins instead. Just simple breath in / breath out. And to keep your mind on air flow.

It might sound crazy, but try this.
All negative personality aspects appear then you totally submerged in thought, that you are your mind. Your main goal is to separate mind form yourself. When you will find this distinction place, lot of bad qualities will subside.