NO Coop, you shouldn't leave AFF. Take a break if you need one, and come back refreshed.
I agree with several others who have said that you need to get over the bitterness against the UPC-- God forgives & forgets-- you should do the same.
You need to find a good church and attend with your family... There ARE other churches besides "UPC" churches that teach the truth. Pray for direction-- and the Lord can lead you to one.
You need to be using the great musical talent that God has blessed you with.... There are many churches that would like to have someone with that talent.
I'm praying for you and your family.