When the date is reset as you describe, one of the ways it can happen is when the battery is disconnected. It may be that there is a poor connection inside your MBP or the battery is totally discharged or 'dead'.
When you borrowed your friends charger, how did the MBP perform? What model MBP does your friend have?
What model MBP do you have and what model Macbook does you husband have? Is his charger the same as your original one?
Go to System Information>Hardware>Power and post this image from your MBP per this example from mine:
With my friends apple charger eveything was totally normal. Her family all have macs from different years so i'm not sure which charger she will have leant me (i'm guessing it would probably be quite a modern one though as they always have up-to-date kit!).
My husband has an old macbook, from roughly 2006/2007, the charger he is using now I bought from amazon quite a while ago. As I mentioned, he has had no problems with it but I did. Before I had these problems I re-ordered the same charger for me as it had been pretty good.
So my macbook pro was fine with a proper apple charger, then it broke and i ordered a new non-apple charger, in the meantime borrowed my husbands non-apple charger a couple of times and my computer kept cutting out. Then borrowed a friends proper apple charge and had no problems at all for a whole week. Then today my new non-apple charger shows up and so far my macbook pro has cut out 3/4 times when plugged in. Totally fine when unplugged.
Thanks for your response, I hope this is clear!
Your battery has seen a fair amount of use but still is servicable. I always keep mine connected to AC as much as possible with a monthly discharge to about the 40% level. You may not be able to do so but if you can, I suggest you do so.
The fact is that you have the solution to your problem. Since your MBP operated normally with your friends power adapter spend the $79 and get one from the Apple store. Third part Apple peripherals are often inferior knockoffs and at times can be more expensive in the long run.