God Choosing Us?

I read this verse in Ephesians and I have tried to do some research on the topic and I really cannot make up my mind and how to understand the whole thing.

Ephesians 1:4 - Even before he made the world, God loved us and chose us in Christ to be holy and without fault in his eyes.
What I do understand is that God did choose us. There is no way that we chose Him. Even before the creation of he world, God chose us as His people. We were selected to be His family and partake in Christ's salvation.

First question I have.....What did God select us from? We're there a bunch of people that were rejected and we were chosen?

Surely not! God is a loving God and He would never ignore some people and allow others the choice of freedom.
My understanding is that every person that was created is chosen, otherwise they wouldn't be created. But then the choice is left up to us whether we want to accept Jesus Christ as our Savior and partake in the good news of Christ or to disregard the whole Christian faith as garbage.

If we look at 1 Corinthians 1:27-30:

But God chose the foolish things of the world to shame the wise; God chose the weak things of the world to shame the strong. God chose the lowly things of this world and the despised things—and the things that are not—to nullify the things that are,  so that no one may boast before him. It is because of him that you are in Christ Jesus, who has become for us wisdom from God—that is, our righteousness, holiness and redemption.

Ok so God chose all sorts of people to be apart of His church. We not all made the same. Seem weak and some strong. By all made for a purpose. It is because of God that we were created. It was because of God that we will be saved. Only God. Nothing we have done or ever will do will change Gods love for us but what it will change is our destiny.

God created us with the bigger picture in mind. He wanted us all to be saved and partake in the good news of Christ, but after that, the decision is ours. What we do with our life if purely up to us. God does not interfere.

But this partly doesn't make sense to me. Why would God create us to partake in the good news of Christ when He very well knew what would happen to some people? Just doesn't quite gel with me so well. (More praying to God and asking Him to reveal to me I think.)

God puts the desire into our hearts. A desire to accept His son Jesus and grow our relationship with Him. Whether we choose to do that is our concern....I think.

John 15:16 - you did not choose me but I chose you.

Ok, so we know God chose us right? Look down further to verse 19. It goes on about That we were chosen "out of this world".

Does this then mean that God chose some of us to follow Him and put a desire in our hearts whereas others He just leaves and doesn't care about putting a desire in their hearts?
The world, we know is evil and we are apart of this world. So I can understand when Jesus says that He chose us out of this world....but the big question is...what about the rest? What about other people?

If we were chosen, then there must be others that weren't?

I would love to hear some opinions, comments and thoughts on this as it really confuses me.

Maybe we aren't supposed to know.

Blessings...