WOW! I would assume that the efforts you've undertaken in buying this home- visiting lots of properties, negotiating the price, paying for inspections, and the appraisal would mean that you have created an emotional as well as financial commitment to this new home.
Title companies are closed today, as it's a holiday, I suspect. But if you have a legitimate reason to cancel this contract, I would contact an attorney, as well as your realtor. You would, of course, be expected to surrender your earnest money deposit as liquidated damages if your contract is standard to CA law. The bigger question is why this came up so late in the transaction. When you speak to an attorney, please make sure and take the whole contract, including if you signed documents such as required in a short sale that commits you not to sell the property within 90 days of purchase. All of these factors would need to be discussed with the attorney, not just the base residential purchase agreement.