Am I required to depreciate my rental property, especially when you lose that depreciation against a capital gain, when you eventually sell the property?

[PatriciaV]

Unfortunately, the IRS rules require you to include accumulated depreciation for your property when it is sold, even if you did not take the expense in prior years. In most cases, it's of greater benefit to claim the depreciation expense while the property is being rented to reduce your taxable income each year.

Here is the reference: 

Rental Property IRS Pub 527 Claiming the Correct Amount of Depreciation "If you did not claim all the depreciation you were entitled to deduct, you must still reduce your basis in the property by the full amount of depreciation that you could have deducted."