Should I break my arranged-marriage engagement?

25M engaged to a 24F. We're of South Asian Muslim backgrounds so our engagement was semi-arranged, and it's been 3.5 months since. When I first met the girl I liked her and after only 6 Skype chats and three meetings decided to get engaged to her, and our marriage is in August and already in full swing of being planned. I won't actually see her again until the marriage because we are in different countries. But now I'm having serious doubts that this was the right decision. Let me list these doubts for you.

1. I am not attracted to her sexually, even though everyone says she is beautiful. This is probably because I have no idea what her body is like, since she adheres to Muslim dress standards which means loose clothing all the time. I've never actually seen her body shape properly. I can easily develop sexual attraction for the girl sitting next to me in class because she's in tight jeans and a t-shirt, but with my fiancee, I have no idea. I'm scared I'll find out on the wedding night that she has a body I don't like.

2. This is a big one. I'm actually agnostic and she is a practicing Muslim, but I don't think she or her family realize this. I have told my parents that I want to tell them, but they tell me not to bring it up and to just say I am a non-practicing and nominal Muslim. I went with this at first because I liked the girl, but now I realize this could cause a lot of problems later as I'd rather not pretend to be something I'm not for my whole life.

3. It's going to be a long distance relationship for three years. She is a doctor and got residency about 5 hours drive from where I will be going to school, in a city where it will be impossible for me to get a job in my field. I asked her if she intends to transfer her residency to where I will get a job, and she got offended and said no. So it's going to be a long distance relationship for 3+ years.

4. I'm starting to resent her. My parents are really thrilled they found a doctor wife for their son, since they were so disappointed I didn't go to med school or become a lawyer or anything South Asians consider great. Now they go around parading this fact in front of everyone, barely mentioning what it is that I do. As a man, I don't want to live in the shadow of my wife, and I know she will probably earn 3x as much as me and this has begun to bother me.

5. I realized that I may want to work outside of the US, but being married to her will make it necessary that we are at least a few hours plane ride away so we can see each other at least once or twice a month, which means I can't accept any job opportunities outside the US. I work in international development and forgoing the opportunity to work outside the country could be a bad career move if such opportunities arise.

6. I don't really feel any liking for her anymore. I think as I've gotten to know her more, I've realized we are very different kinds of people, and she's not the type of girl I usually fall for.

These all seem like pretty big reasons, but what stops me from breaking the engagement is the loneliness I know I would feel if I didn't have anyone, and my weariness with the dating world. I'm also worried I'll never find a girl as good as her, who has such a great career, comes from a good family, and is good natured and quite beautiful. My parents tell me that I'll never get a girl as good as her, and that I'm really lucky to have gotten such a girl, and that I'm not even in her league but somehow I got her. A part of me believes them and wants to feel grateful for what I have, but a part of me also feels resentful that they say this. I know she's the type of girl that would never cheat, and who would always be willing to work through problems and keep up her end of the bargain. Despite that she seems like the perfect person on paper, I can't help the way I feel.

Everyday I see-saw about whether to break the engagement or not, but the time has come for me to make a decision, because the wedding day is getting closer and closer. Do you redditors have any advice? Have you dealt with any of these feelings before? Can you share any stories that will help me make a decision?

TL;DR: I am engaged to a pretty, good natured, female doctor who comes from a rich family, a real catch, but I hid the fact that I don't believe anymore in the religion we were raised in, and now I also realize I want to work in a different country than where she will be, so I have to decide whether to break the engagement or just go through with it.