All of this advice posted so far is sound, and worth investigating.
I have had difficulties with intrusive thoughts, and it can be a symptom of OCD indeed, and often a type of OCD called Pure O, meaning pure obsessive.
Learning to meditate can be very beneficial to your state of mind and also body.
Meditation can be wonderful and bring about amazing feelings and great changes in confidence and self esteem - you can benefit greatly from trying this.
What helped me with intrusive thoughts is using a white chestnut flower remedy, which is for intrusive thoughts, and also one fish oil omega 3 tablet a day.
Obviously, general exercise helps with body and mind too.
Humans are flawed and thoughts exist; it's just negative energy though - don't panic, because it is not you.
Letting the thoughts persist and do what they do in your mind whilst ignoring them and not constantly ruminating for a meaning or reason, is the way to go about this. I know it is tempting to fight the thoughts, but try not to, and do not worry about them and the scary nature of them.
A very nice day for you sir.
*Hug* Feel well.
x
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and the life of the candle will not be shortened.
Happiness never decreases by being shared.