Seems like the two major points you are interested in are:
1. Priesthood authority
Here is my attempt an an answer:
First, priesthood authority. It _is_ true that Jesus called the Twelve Apostles and laid his hands on them and ordained them. And, it is true that when Judas Iscariot went bad he was replaced and the remaining eleven selected one by "lots" and "hew was numbered with the others." But no mention is made of laying on of hands in that case. And the Bible never teaches that the way people get the authority is specifically through "the laying on of hands." There is nothing magical about that. If Jesus said they were ordained, the were ordained. We do lay hands on people to pray for them, but that tradition is not mandated by the Bible. So it is exactly that, a tradition.
Where does authority come from, according to the Bible? It comes from faith. Even Jesus said that in some towns there was not much faith so there were few miracles. There are only two kinds of people in the Universe: saved and unsaved. When we are without faith in Christ, we are unsaved. Faith in Christ makes us saved and makes us children of God: John 1:12 "But as many as received him, to them gave he power to become the sons of God, [even] to them that believe on his name:" If you are actually a son (or daughter) of God you have all the rights of sonship.
So, you are right, the Church is made up of all born again believers in Christ. The greek word used in the New Testament for "church" is ekklasia, which means "the called out ones." The word apostle means "one sent with a mission). There is not electrical energy that needs to be passed on in order to be a child of God, rather when one believes God about Jesus, our faith pleases the Father.
Apostasy comes and goes. Some people say that Salt Lake Mormonism is apostate from the teachings of Josep Smith and Brigham Young. I agree with that assessment. _Real_ Mormons _must_ practice polygamy, because it is the _New and Everlasting Covenant._
The Christian Church experiences periods of falling away, or weakening, but the Gospel message as contained in the Bible has never been lost. And in any age and in any land, where people receive Christ into their hears by faith, the Church is reborn. You are right: "Whenever two or three are gathered in my name, I am in their midst."
So, it isn't that the Catholics are "The Church" or the Protestants or the even the Mormons. It is, rather, "Where is the truth about God taught?" That is where Mormonism fails miserably. The Bible is not hard to understand. Mormonism totally jacks it around, distorts it, adds to it, subtracts from it. So, even if some Mormon somewhere is actually saved, the point is that it is _in spite of_, not _because of_, Mormonism.
Hope that helps a bit.
I am going to send you some teaching CDs (let me know if you _do not_ have a CD player). And some DVD videos.
If you have other questions, fire away. And, I hope you will email Sharon and/or Jeanette. They have been where you are in very recent months.
Also, I am going to post this letter on my web site. However, I will not identify you or where you live, to protect you privacy.