Anyone who lies that badly is trying to deny they have lost.
If you’ve walked into a poker game and holding a Full House...having put $5,000 down on the table, your most significant risk here is that someone else at the table holds four of a kind or a Straight Flush. Most folks would continue to sit at the table and even double-down on the bet.
In this case, Pelosi was awaken from slumber and now realizes (maybe for the entire past three months) that McConnell actually holds a Straight Flush, and there is virtually no way to lessen the lost money situation.