There has been some confusion over these seemingly identical perks, with some people getting "Free Spirit" auto unlocked and others not. I was curious about this myself, so I took a character with 0 in both for testing. What I found was that for "Free Spirit" requires completion of the crypt quest (kill 50 zombies, strength, woe), while "In Memoriam" only requires running to the end and killing woe. For Shadowboxer, I only killed woe, while for Tiger, I did the full crypt quest, and the results are clear: