Can no longer play Origin version of Titanfall that is currently installed.

I own Titanfall (2014) on my hard drive. Titanfall (2014) via origin. I saw it was on steam and I purchased it there a second time. Now I can no longer play the already installed Titanfall game on my hard drive. Origin will not let me. It says I have to install the game. I am essentially locked out of my owned content that is literally installed in my programs folder. I own in my library Titanfall and Titanfall Deluxe Edition, two separate games via separate purchases, one on Origin and the other on Steam. I should be able to play the game that is currently installed on my hard drive, without having to uninstall the game and reinstall the "Deluxe Edition". I know this a strange circumstance, but it just kinda bothers me that I can not play a game anymore because I bought a second copy.