Hello and welcome. Your wife sounds like a lot of people who have a problem, try one solution and than give up. Most of us here have had to try several medications to get results and even more are still adjusting the meds to "fine tune" the results. Unfortunally its quite common for bipolar people to go off the meds. Either they dont work at all (rare) or they just numb us out ot everything and we feel like we are moving thru molassis and have all the emotional range of a houseplant. This is tough because in her mind, she is fine. She can completely justify everything she has done or will do because her brain will help her rationalize the issue so it makes sense to her. Trust me, it does.
Now the hard part. You cant make a BP get help and start meds. They have to want it and even then its really hard to wait for the drugs to kick in and provide relief of some sort. This is something you can talk to her about but if she is dead set against getting on meds than things wont change and will possibly get worse. We dont get better with age, this becomes harder as we get older.
Wish i could have been more positive but right now you need the truth.