I'm also Christian (Protestant) and grew up believing that God directly influenced every part of my life and if life isn't going well, then I'm doing something wrong. I no longer believe that. I've seen enough of life to know that how our life is is affected not only by ourselves but also by circumstances. I don't see God's hand directly in any of it.
I do see God's hand helping me to live but He allows me to make choices that then influence how my life goes. And.....my choices are there to help me learn and grow. There are choices that make life more difficult but I always learn from them. In that regards there are no wrong choices; only choices that don't work for making my life comfortable.
I strongly believe that God is not punishing you and that he is by your side helping you thru this if you believe that He will help you. It's our attitude that determines how close we are to God and how we manage when negatives arise in our lives.
I believe that God allows natural consequences. For example: we make a habit of drinking every night, become alcoholic, lose our health or our job. Not because God caused this to happen. God allowed it to happen. We chose the path that led us there.
We learn skills along the way that help us make better choices and handle the choices we make. I could say that God has a lesson for you in this instance. But it's not a lesson, such as should've gone to church more, unrelated to the event. Perhaps the lesson is to have more faith that everything will work out for the good. I see good in everything I experience, even when the experience is painful. The good is that I learn a lesson or two or three.
I do believe that jealousy is a "sin" tho I don't believe in sin in the traditional way. The way we feel or the way we act determines how are lives are lived. When we do something counterproductive to our own well being and happiness we have "sinned" in the Biblical use of that word. I see the Bible as giving us similar lessons as some of the more modern psychologists. The language is just different.
Jealousy makes you unhappy and hinders your loving relationship with your sister. Perhaps the lesson in this is to learn to accept life as it is, feel compassion for yourself and to let go of the jealousy of your sister.
J doubt that you did anything to cause pre-eclampsia just as your sister didn't do anything that prevented her from having pre-eclampsia. The pre-eclampsia just is. What our attitude about it is up to us. We can improve our attitude with faith in God. God will help us cope.
I don't think of God as a person. He's a Spirit that can reside within us if we want Him to. That Spirit becomes a part of who we are. That Spirit allows us to have faith that everything will work out for the best. The Spirit is positive and doesn't punish us. He teaches us and guides us as we make decisions and live our lives.
Going regularly to church may be what will help you deal more effectively with your life. If so, then this can be a lesson to teach you to begin going again. But your pre-eclampsia isn't punishment for not going.