What a bad mood I am in.

It's terrible to be suspected of lying.

Why not try to trust others? 
Fine! (insert a space here)Whatever!

Try not to be too angry or hurt, this is a passing moment, and there is a chance that there is a misunderstanding.
If someone has decided not to believe in you, perhaps they are defending themselves because of a previous event which hurt them, and they don't want to be hurt again.

I would be hurt too, if someone didn't trust me because I know the strength of my character and my honesty, but unfortunatley not everyone is as worthy of trusting as you and I.
X

How the bad mood I am.

It's terrible to be suspected of lying.Why not try to trust others? 
Fine!Whatever!