If you had a closer communion with the Church, you would know it. But although you have a relationship with Christ, you believe that coming under the authority of the Church is unnecessary. For most of their history, the Protestant denominations also believed in being open to children, and were absolutely opposed to birth control. Martin Luther made a big deal about "Be fruitful and multiply." Acceptance of birth control is a new thing for Protestants. Here is a good website on the history of Contraception and Protestantism.
In fairness, I know lots of Catholics with smaller families these days. I believe that there are numbers of factors that come to play here, and it is not simply a matter of disobedience. Our capacity to support large families in the west is diminished, partly dues to social expectations and improvements in lifestyle. These days in Australia children pretty much regard it as child abuse not to supply them with a mobile phone and a laptop and a ....... . I don't imagine it is much different in the USA or Europe. Reduced propagation rates is statistically consistent with improvements in literacy, general education, and increased social mobility.
For the wandering tribesman with poor health outcomes, significant external threats and poor nutrition, propagation is vital for the survival of the tribe. "Be fruitful and multiply" makes perfect sense in this situation (and infant mortality was high). Today, and certainly in the western world, we have great health outcomes, reduced external threats, and some of the best nutrition ever (possibly even over good - we face national obesity problems - and our average height is perhaps between 10 and 20 percent higher than only 100 years ago.
We also now face climate change when one of the identified causal conditions seems to be very clearly over population, deforestation to support it, and over cropping and over farming. Basically we are not giving the earth a chance to catch it's breath.
Is the command 'be fruitful and multiply' for all time, or for a time? I certainly wish we could loved one another as faithfully as we have been fruitful and multiplied.
I am not a protestant, I am a small c catholic, and as I understand things the ultimate guide for a catholic is the informed conscience. Do I listen to the Church? Yes I do. Do I use the intellect that God has given me? Yes I do. Do I care about the Scriptures and the Traditions? Yes I do. And I am still left with the question - for all time or for a time?
On balance I think I come down to understanding that it is for a time, and I am open to the idea that the universality of that time is not past. I am not completely convinced either way, and I do see it is important for people to find the truth that is the truth for them in their time.
I hope I have been fair. I have to be honest and say I find this statement of yours a bit harsh "you believe that coming under the authority of the Church is unnecessary" and probably not a realistic understanding of the position taken by
@Strong in Him unless all it really says is 'if you were a good Catholic girl you would think like me'. I think we do better when we listen to each other, and I know I have had much to think on in what you have posted, however I know this, that Catholic Obedience does not simply mean agreeing with everything a Pope/Bishop/Priest says, Catholic Obedience includes informing ourselves as best as we are able to make the best decisions that we believe that God would have us make - and sometimes that may mean saying, 'I am sorry Father but in true faith I have to conclude that the truth for me is not as you say'. There are many good and faithful Catholic people who have in all honesty come to this position on birth control, and sometimes they deserve to be supported.
Now I understand from what has been posted that this is not the truth for you, and I accept and acknowledge that. Indeed I am glad that with a true and faithful heart you have found solutions that work for you. Those solutions do not need out of hand to be everybody's solutions. And to conclude, let me assure you I don't think any of this is easy.