I'm having a problem trying to believe in the existence of Satan for many reasons. It's like his existence logically contradicts the popular view of God being a just God.
Satan is believed to be a former high angel, who fell from heaven because he either hated Man, rebelled against God or both. Now, this world is a suffering world.. we die, there is pain, there is evil, the world is just damaged because sin entered it through Adam and Eve. Adam and Eve fell into the temptation of the Serpent, so the serpent is accepted to be Satan which means his fall pre dates the Garden of Eden.
So here is the problem, if this world became what it is because of Adam and Eve sinning, then why didn't heaven get the same results if the actual first sin was done in heaven - through Satan?
There is more to this question, but i'll just start off here because every religion forum i've been to can't answer this.
You seem to be discovering theology.
And don't worry about thinking for yourself: it's ok for a Catholic to think for himself so long as what he thinks is in agreement with the Church. Actually, that's not strictly correct. It's so long as what he teaches others is in agreement with the Church. So by all means go ahead and think through this stuff but it's best if you don't talk about it or else you will get a gentle visit from your priest and if the worst comes to the worst, you will also get a visit from your bishop and it will be the last one you get.
I'm sorry that other forums didn't give you the answer. (Although I might suggest that perhaps they did give you answers but you didn't like the answers.) In fact the Catholic Church has all the answers you need. But you don't really need any answers at all. It is sufficient for you just to be a Catholic in good standing and you are deemed to be in possession of all truth and righteousness because you are a member of the Church. Though I guess you know that already...
Anyway, I was saying. Oh, yes, there is a fellow Catholic of yours in this forum called Cruciform. He is an expert on where to find all the Catholic teaching on every subject under the sun. If it's Catholic you can be sure he either knows it or else he can tell you where to find it. I just thought I'd mention that because you might get along with him well.
As for me, I used to be a Catholic myself. But I decided after much thinking that thinking for myself was a fundamentally good thing and even though I was a much more faithful person than most other Catholics in my parish or indeed elsewhere, and I went on all the pilgrimages and said all my prayers and helped with the local poor, etc. and I went to early morning mass before work and school because I loved Jesus so much and was often just sitting contemplating the Remonstrance, but despite all that, I'm afraid that thinking for myself led inevitably to that visit from the local priest, who I have to say, knew Jesus a lot less than I clearly did and hence he was unable to have a proper discussion with me. He had his rules and I have to admit that most priests would probably do the same. I didn't really blame him for that but it was clearly inevitable that I had to be the one to go because, as I said before, it is ok to think for yourself so long as you only think what the Church also thinks.
So back to your subject.
You said:
Now, this world is a suffering world.. we die, there is pain, there is evil, the world is just damaged because sin entered it through Adam and Eve.
Although this is not your central and highlighted question, I think it is more fundamental. Many people, including you apparently, perceive suffering and pain as evil things. But suffering is necessary to define us as individuals. We only experience joy because we know there was a possibility that it could have turned out differently. You experience happiness when you win a bet but you experience frustration and hurt when you lose a bet. You feel happy when your stomach is full but you feel pain and worry when it is empty. You feel satisfaction when you are with your loved ones but loss and bereavement when you are separated from them. None of this is evil. You feel these things
because the possibility of the opposite happening was real.
If money grew on trees, so to speak, you would not know any of these feelings. These feelings are necessary to define who you are in a world where anything could happen. They set the boundaries of your personality: if some random person on the other side of the globe dies, it means nothing to you. But if your wife or husband dies, you lose a part of yourself. It is the same as having a leg amputated. So the boundaries of your personality are defined by what makes you joyful and what makes you feel pain. Without them you could not be a person at all.
I ought to stop here for now in case the mods decide I have been wittering on too long. We are supposed to be reasonably brief and communicative here. But feel free to comment and I'll talk more about your questions.