The fact that you are both willing to abstain completely may actually mean you have a call to a Josephite marriage. Do not punish yourself over this; there is nothing inherently wrong with abstaining from sex by mutual consent. Your feelings about becoming parents are so strong, I’d say it is a serious thing to work on before becoming parents. You ought to work on it, whether or not you do become parents, but don’t put the cart before the horse. You are renouncing two of the great goods of marriage, though, so it is good that you are willing to work on this. Work towards either not renouncing children and marital relations or else renouncing them from hearts that have also renounced the less praiseworthy reasons for doing so.
One step at a time! You might try just trying to see children as precious people, and your difficulty with their energy level or maturity level as something you need to work on in yourselves. Maybe you two had difficulties with other children when you were kids, and you need to work through that. Try seeing their parents as people who are willing to do work that you aren’t willing to do yourself, and work up an appreciation for them. When you get old and need care, it is their generosity that will have put people in the world to do it! At any rate, try to get over your unhappy prejudices, and go from there. For the time being, you are doing nothing wrong by abstaining from sex. To the end that your attitude needs improvement, well, we all have something like that. You will not get better by beating on yourself. Get better by trying to see children and their parents in a more positive light.
Do see a spiritual director, though. You are attempting something difficult to do in the long run, something that could cause regrets later on, and you should not go through it alone.