Re-key a lock so it's always openable without a key
An actual locksmith can do that for you at sane cost.   Remove as much of the lock mechanism as possible, and bring it on into a shop.  

He can also make it a deadbolt, so it can't "autolock behind you" and will only lock if manually operated.  You can also get a double-face lock so if they break the glass to reach in, all they find is another key-face (this is OK if it is not an emergency egress route).  In my house we never use the autolock, we only deadbolt.