Couldn't lie straight in bed Australia New Zealand informal
To be dishonest or deceptive; to lie a lot
Don't care about what John has said. That guy couldn't lie straight in bed.
No one believes what she is saying to be true as she couldn't lie straight in bed.
White lie
Seem to be very suspicious or morally unacceptable
Used to imply that someone is acting as if he or she is demure, innocent, sincere or reserved but they may be not
Very dishonest and deceptive
people often do irrational or foolish things when they are in love.
I and my boyfriend have decided to get married in the summer. I don't think that's wise, since we won't have enough money saved by then to set up house. But then, one cannot love and be wise.