Your pursuit of Catholicism is amazing. The only thing I could say (bear with me for just a second just try to imagine that you believe what the Bible says for the purpose of this response) is that no matter how hard we “try”(by our own efforts) to have faith (which it sounds like you truly went all out and poured so much into it)
We cannot come to God on our own. “
No one can come to me unless the Father who sent me draws them, and I will raise them up at the last day.” (John 6:44) (We can assume the Father draws us through the Holy Spirit who “leads us to all truth”)
I’ve had times where I go through the motions out of fear of Hell or because I feel it’s an obligation, and certainly moments where I doubt. (I am not saying this is you
at all,
only me personally) This will not lead to faith, my effort may please God, but only He can draw me to Him and allow me to believe.
I’ve given up, stopped praying, and tried to walk far away from God. I felt like I did everything I could (praying hours on end, fasting, sleeping on the ground, spreading the word each day, etc) and yet I felt I made no progress spiritually and I wanted to give up and wished I never even heard about God. And some of the doctrines confused me and it seemed to make no sense, as well as the endless amount of beliefs out there, how is mine correct? Every time, after however long God allows me to try to hide from Him, I can truly feel the Holy Spirit pulling me back. It’s a gentle love as if saying “I am here, and you must persevere because even when you can’t feel it I am holding you up and I will not let you go. If you leave me, you have no hope, but I want to save you” I’m not making it up, truly, if I had my way, I would not even believe right now, I have tried to get away from God so many times and find “better” things living my own way.
He will not let His children fall away permanently (even though we may all have our moments of doubt and try to run away like Jonah

, even perhaps for years, He will always welcome us back) because He loves us. Jesus says “
All those the Father gives me will come to me, and whoever comes to me I will never drive away.“ (John 6:37) We must sincerely ask Him for faith. He does not want us to disbelieve and He does not want to send us to Hell. He may wait awhile and let us go through rough times before answering our prayer, but in the end He will not refuse us salvation if we come to Him and plead with Him. It says this in His Word, He will not drive us away and deny us.