You sound happy in your circumstances. But recognise that you have been lucky - and that yours is not the experience of many many women and men (including myself) who have sexual relations outside of marriage, something I believe contributes to the large number of abortions.
The fact is that the church ministers to millions of women and men throughout the world, not all of whom have your luck (or indeed mine). Even though the probability of what happened to me is very small (like winning the lottery) you multiply that over the number of women in the world and failure rates are a not insignificant problem, and lead to a great deal of suffering. The rules that it makes are clear and uinversal. We may think, oh but that doesn’t apply to me, or that will never happen to us, it is irrelevant. Well, it does, and it can, and it isn’t!!
People must be free to make their own choices. Even many within the Catholic church make choices that run counter to the doctrines they have been taught (of course, a lot depends upon parents and teachers - when I was growing up, my parents were extremely scrupulous about bringing me up with a Catholic conscience, but although I went to Catholic schools, I had quite a few teachers whose attitudes towards sex and relationships were decidedly more relaxed than my own).
The fact is that people are going to make choices, and no matter how hard the church - and the religious right in general - tries to clamp down on the ease with which those choices are available, all they mostly succeed in doing is withholding information that might alter the choices people make. Consider the cultural norms that exist in some developing countries, where women are expected to submit to sex whenever their husbands desire it (and where women are considered objects to a far greater extent than they are in the supposedly decadent West). Either the women must cope with an endless round of pregnancies, and then face the difficulties of raising their children in a largely unfavourable environment, or they can try to take some control of the situation. Resistance may very well lead to rape or other forms of assault, so birth control could be a useful alternative. Trouble is, many moralists in the West want to refuse access to birth control in these circumstances. This doesn’t exactly allow the women much exercise of free will, does it? Fair enough, it may be a band-aid measure, but cultural change takes a long time to effect, and in the meantime…
In any case, the further point I wanted to make was that I am very well aware that choices have consequences. This is something else that needs to be built into a comprehensive education, whether about sex particularly or about life in general. One’s ability to cope with consequences - and the nature of those consequences for all persons involved - should inform the decisions we make about how we act. When it comes to the possibility of sex leading to pregnancy, with or without contraception, there are several approaches that can be - and have been - taken.
Lots of people advocate for abstinence-only sex education, which generally takes the view that abstinence is the only practical option, and provides very little actual, judgement-free information about birth control. As a consequence, teenagers often choose to have sex anyway, either through defiance (I suspect that I was the exception to the rule in my lack of teenage rebellion) or simple curiosity about something they haven’t experienced and about which they haven’t been told everything. Bingo - teen pregnancy.
Comprehensive sex education has been shown to be very effective in allowing young people to make informed choices. As a result, they tend to delay sexual experience, and are much more careful about it if they decide to go ahead. Some like to call this value-free sex education, but that doesn’t necessarily follow. It might not contain religious values, but that doesn’t mean it doesn’t teach kids how to respect and manage their bodies, and those of others.
Accepting consequences is much easier if you know what they are ahead of time. Knowing that pregnancy is a consequence of sex, you arm yourself to deal with that eventuality, ahead of time. Can you, in good conscience, use artificial birth control? Can you, if ABC fails, bring yourself to resort to emergency contraception or early-term abortion? Alternatively, are you in a position, emotionally, physically, financially, to raise a child? If the answer to any of these questions is no, then it probably is the wisest choice to refrain from having sex. If you can cope with any or all of these alternatives, then your choice comes down to other criteria.
But as I said before, when it comes to sexual experience, amongst other things, people should be free to make choices, armed with good information and prepared to deal with the consequences of their actions. Sex, perhaps moreso than most other choices we have to make in life, is an intensely personal and individual thing, for which consequences will be different for every person, and in which external agents - be they cultural or religious or both - should have little business interfering. And guidance is very different to interference. Practical advice and honest appraisal is a very different thing from a threat of eternal damnation.