Hi and welcome!

I agree with DE that it might be useful to see some kind of counsellor, if you're not already doing so. Personally I don't think that being bi-polar would influence whether or not you lie. It could equally be said that people with dyslexia lie, or that people with depression lie - lying, from my point of view, isn't really connected with mental illness - unless it takes the form of delusions which would technically cause the person to lie.

I'm not sure to what extent your lying is a problem. Is it something which affects your day-to-day life, so that you end up lying about things there is no need to lie about? Or does it happen under certain circumstances?

I'm glad you posted about this because I too have some problems with lying about things in my real life. I've realized however that (for me) it's to do with fear and trying to avoid being judged or criticized. It only applies to my family though. I'm not saying that I am always completely honest outside of my family, but just that I've realized that I can end up lying for no particular cause. I've come to the conclusion that lying can develop into a sort of habit - you might not need to lie but your mind still makes that switch and so you find yourself thinking/ telling a lie.

So if you can work out what it is that might be pressuring you to lie - then it might help you work on stopping it.