So you didn’t agree with everything at first, but you did research and just just convinced yourself to believe it.
Not to speak for Tantum, but in my case, it was not a matter of “convincing myself” - it was a matter of looking around me, and seeing that the Catholic Church understands reality as it is, and makes sense of it.
For example, I have an unmarried couple with children living with me in my basement. I was thinking, maybe it’s fine for them to be that way; I don’t know. Who am I to judge? But then, the girl let slip to me the other day, “It’s a lot to handle, for me. I am alone in being responsible for these children. It scares me to think that there is no one else on the whole planet who is legally responsible for them - I am completely alone. Their lives are in my hands alone. What if something happens to me?”
Now, is it God’s will for the mother of our next generation to feel so alone and so scared for her children? The Catholic Church teaches that marriage is the proper way to bring children into the world. Is it because the Catholic Church is being a big meanie, and doesn’t love the young man and young woman who are living in my basement?
Far from it. The Church loves that young woman so much, and doesn’t
want her to feel so alone and scared. And God loves that young man enough to want to call him to his responsibilities, and to bring him into partnership with the mother of his children, instead of just being an observer on the sidelines who can wander off any time he feels like it - and miss out on the most important thing in his life.
I suppose that is what we must do, but us being humans, I just feel when rules/doctrines are presented to us, we abide by them the best we can, but there always some that we may “bend” or “break” or not agree with.
I think that over time, you would see the reason why the Church teaches what it teaches, if you are looking and listening and paying attention.