I'll give you a technique for reseting your brain. It works wonders for me.
When you realize you are on a wrong path of thoughts and want to reset your brain, enter a quick emergency meditation by following the technique of Nhat Hanh: When you inhale say "IN", when you exhale say "OUT". You don't have to pay attention to anything else other than your breathing, so, don't bother with positions or silence or anything. Just mark the inhale and exhale in your mind using the words IN and OUT. That's all. A long silent IIIIIIINNNNNN and a long silent OUUUUUUUT.
Try it now for 3 breaths just to get a good idea about how powerful and effective it is.
Use it often and you will get better at accessing it when you truly need it.
"What is love?"
"The total absence of fear," said the Master.
"What is it we fear?"
"Love," said the Master.
I chose Love