I have been in a long distance relationship now for 7 months you think my partner will cheat?

My partner lives in IL, and i in NY, we call each other our true lovers, and we absolutely love each, and talk about our future, about getting engaged in 3 years tops and getting married in 7-8 years tops. My partner is trying to keep things going slow when it comes to engagement and marriage because, my partner always says "We are to young, when the time comes, it comes". Now i have been worried about my partner cheating on me since day 1, and its because i have been through tough relationships in the past that no teenager should ever go through, such as physical abuse, threatening and cheating. But the person i am currently with is different and has changed me as a person, stopped me from doing alot of bad stuff, and making me a good clean, nice individual. My partner is very sexy and works out, has a great body etc. This is what makes me scared though, my partner is a virgin, which is a suprise to me. My partner as well says "i dont get hit on, no one has ever come on to me, and i have never kissed anyone ever before" which suprises me because of my partners personality and great body. Just from one day we usually txt each other 567 messages, whats even more weird it may sound to you people, but we take showers at the same time, we go to sleep at the same time, we watch TV at the same time together, we do everything together. We talk all night and day on weekends on the phone and skype sometimes. Usually on our monthly anniversaries we write each other letters that we read to each other on the phone. I feel truly deeply in live with my partner, but even though my partner says the same thing to me, is my partner feeling the same thing?do you think my partner will cheat on me?