Catalytic converter reset problem

Computer codes keep appearing on dash. (At 730d right now) It all started with rapid electric lock firing that kept shutting down my battery. Pulled relays, car stared fine, but doors would not lock. Put back in. Car with new battery working fine(ish)
five months later go for smog test. Failed. I was told that catalytic converter needed reset. Said driving fifty to fifty five mph on freeway for ten minutes. Rest for two, then drive ten minutes again and should reset. Failed again. Took to mechanic friend with computer. He said needed to do "drive run" again. Car still drives, but I need to pass smog by June 14th. Ran errands today and car would not start after got home. Neighbor jumped battery and started.

Note: For over a year now, electric door stuck on rapid fire, and occasionally new battery kept draining. So pulled relays. Now eight month old battery drained again. Drained four times prior so pulled relays, could not lock door, so put them back.
Lived with door lock problem and new battery was working fine. Until today when car would not start after several stops around town.
Help! I would really like to understand what is going on and maybe between another visit to mechanic friend with computer on Monday and your guidance, we can get some answers?
Thanks so much! I am learning as I go along and know very little about car mechanics. Kimberly. :)