As a man not being a father, I am of course not qualified to answer this. But I think this subject is bigger than the word “mom”. Guilt is a universal problem that does not only apply to mothers (with or without cf) and their child. So let me point to a broader answer.
As always, the answer is in the question. We need to not look at what we feel guilty about (could be anything), but to the question: what is guilt? Where does it get its energy from?
Guilt implies, that something is perceived as wrong. We never feel guilty about something good (unless it is too good, but in that case, it is more that we are a bit ashamed of having so much luck, which is different from guilt). Don’t worry about this type of guilt, life will take care of it soon.
So with real guilt, we either think we did something wrong, or should have done something but wrongly did not, or some situation is wrong without our doing but we associate with it.
In case of having cf and feeling guilty, clearly the latter form applies. We feel or think (which is basically the same, they are products of the mind) that something is wrong. “It should not be like this”. This boils down to a lack of faith in the universe. Something is arranged in a certain way (called: this-here-now), and in our finite and arrogant “wisdom” the mind says: I know better, this is wrong.
Now, there are two possible ways of attack. One is to try and reason with the conviction and somehow make it less true. Your list of 3 mitigations belong to this technique (although nr. 3 holds a key to the second way). It is a form of positive thinking, which is more comfortable than negative thinking, but still a way of trying to think your way out of your problem. Now, this will not be successful as you might have noticed already. The mind is clever enough to find other thoughts to sabotage any positive turn you might have thought of. You will never find an answer this way, it will turn out to be a ping-pong game with the mind, your mind will enjoy this enormously and there will be no end to it. It will cost a lot of energy and will go on for the rest of your life. All this energy will not be going to you or your child or to being in general, it will go wasted.
So, the second way is to really take a good look at this conviction and debunk it. Not fight it, not mitigate it, but totally erase the ground under its feet. This requires a change of heart. As long as (secretly or clearly) you think of cf as something wrong, something that should not be like this, that the universe made a terrible mistake with you and now your child is suffering from that, your mind will be able to construct some guilt from this in some situations. And being a parent is an easy terrain of course, because almost no parent feels totally comfortable about how he/she raises the child.
So, this mom-guilt your talking about is always preceded bya personal conviction, that because of cf you are not the perfect mom that your child deserves. That somehow, your child misses out on something or someone better. And that it should have been different. Now, ask yourself (a couple of times if needed): is this true? Is this really true? And with every answer your mind comes up with, ask again: is this true, is this really true? Go on asking until your mind does not come up with anything anymore and has to concede: I don’t know. Mostly, after 3 or 4 rounds of questioning the mind is out of ideas.
Now, only this last answer is really true.
So, as soon as you accept that simply you don’t know and be comfortable with that, you are aligning with life again. Try to have some faith. Not in some particular outcome, but faith in general, faith in life. Don’t look at this situation as a mother-with-cf having a child-that-might-or-might-not-get-the-perfect-upbringing. You are just a mother with your child. You just don’t have that control at all. It has nothing to do with cf. There will be times that miraculously you find the perfect interaction with your child in some situation, and there will be times that no matter what you do or don’t do, things turn out a mess. They might be related with cf or not. But there is no way and need of knowing, and no need of worrying about this in advance or looking back. Enjoy the play, it is not supposed to turn out a certain way, and if it is, you wouldn’t know it.
The only thing you can do, is act out of love for both yourself and child as often as you can. And be comfortable with the truth: you don’t know. Life knows, let it take care of itself. But you know that you love your child, that somehow it was predestined for this child to have you as a mother and for you to have it as your child. How wonderful! Now trust that this is the perfect situation for you and your child, it needs no changing at all, no one is at fault and nothing needs to be improved, mitigated or cured. Who are you to question this, to be at odds with it? So don’t go mess about in your mind with this predestination. Don’t deny life. It was meant to be this way. You have no clue why and what you and the child have to (and will) learn from this. Don’t try and figure out what your journey is all about. Just go along with it. Dance your life, don’t think it. You both will do fine; the universe is great in dancing and you are it.
So anytime your mind comes up with this guilt-trip, question it until it says: I don’t know (for sure). Then (or right away, after a while you don’t need the questioning anymore and the answer will pop up immediately) kindly thank your mind for its suggestion (don’t condemn, it knows not better), and say: Me and my child are the perfect mother-child situation that the universe could come up with for the both of us to experience (see how this is an absolute truth!). I will not question this and I will not tolerate my mind trying to do so without correcting it and bringing it to this truth: Everything is exactly as it should be.
May grace be with you.