Stark, you must have gone through some painful stuff. You really might find it valuable to talk to a knowledgeable Catholic or a priest, because you have gotten an earful of falsehood from somebody. I am grateful that you are starting to sort out what's true and what isn't.
This may provide some clarification:
(1) If anybody told you you are going to hell because you are not Catholic, they are liars. But now you know that.
(2) If anybody told you that all couples who are not married in the Catholic Church, are living in sin, they are liars too.
(3) The concept of "illegitimate child" or "bastard" is not found in canon law and the concept does not exist in the Catholic church. The term "natural child" is used in Canon law to refer to the child of unmarried parents. The entire context is to secure the child's right to his parents' support and nurturance whether they are married or not.
Do not let ignorant people inflict pain on you. And please do not abide in these falsehoods any more.
Why'd you pick all the gloomy stuff to believe? (and all the dumb bigoted Catholics to learn it from?)
Heck, my dad had a "wife still living", as they used to say, when he and mom got hitched,but somehow 48 years later, give or take, I became a Catholic and, if you leave out some of the worst and sappiest hymns ever inflicted by banal and maudlin musicians on an unsuspecting populace, it's been great! And recently my parish got a WONDERFUL organist with actual TASTE, so now the music is good too!
Being Catholic (or hanging around Catholics) is no excuse for not thinking. You gotta use the wits God gave you. And one way to do so is to make sure you go to a parish with priests who love Jesus and have two wits to rub together. Don't listen to that other B.S.! This whole world was made by "the Love that moves the sun and other stars" and if you were the only human in it, and you needed God's Son to die for you, He'd do it in a heartbeat!
There are still plenty of people who think I'm illegitimate, and on my own toot I AM! Completely! No intrinsic redeeming characteristics whatsoever! None that aren't tainted by sin, anyway.
But for some reason, I keep hearing God say, "Once you were no people, but now you are MY people!"
I bet if you keep listening, you'll hear it too.
Excuse me. I have these fits occasionally.