Are you overdriving your headlights just a bit here?
From everything you've said - I don't see that she's eager to rush into a sexual relationship. (Perhaps she is, but it didn't come out in your post.)
And when you say,
...she knows that i dont care about sex and i'd rather wait til marriage anyway...those were her original plans too but then again things happen...
I have to ask, "Why change your plans?". Have you REALLY thought through what you're doing? You're dealing with something that a lot of people consider to be very significant, and very special, and something you can never cancel nor repeat. Your "uncomfortable feeling" about an experienced partner supports these views - if it WASN'T significant, it wouldn't bother you like that.
Then there's the long distance nature of your relationship. That situation is stressfull for couples who have already established their commitment, and even more difficult for those who are trying to get something started.
Introducing sex into a relationship (at any age, but especially at your age) tends to stop further development of the relationship. Ask yourself, have you and your girlfriend REALLY become as close, and intimate (in a non-sexual sense) as you'd like to be? There's a lot more to it than talking on the phone (though I admit that's a start). Sex can be a way to solidify what you two have already achieved between you, but it won't make up for what's not already there. Unfortunately a lot of people try to use sex as a way to get, or keep, a boyfriend or girlfriend when their relationship doesn't have a solid basis, or is already stalled or starting to come apart. They seem to feel "If only he/she knew what a good bed partner I am, then he/she would work harder at staying together." but the results are often the opposite.
I wish I had bookmarked a web page I found a couple years ago. As best I recall, it reported a university study about factors that contributed to long-lasting relationships. One of the findings was that people seldom stay with their first sexual partner - something like 2/3 to 3/4 of their respondents had broken up with the person to whom they gave their virginity within a month of the event. Many of them indicated that sex had actually contributed to their breakups.
Because of the distance factor you're up against, you run the very real risk of sex becoming the major thing defining your relationship. It will tend to become the ONLY thing you two experience together. Sooner or later one of you will get the idea that it's the ONLY thing the other one is interested in. In the end you may re-inforce your G/F's negative experience.
I think you & your G/F should spend time together when you can, and use phone, email and paper mail to bridge the times between. (Hint: If you want to REALLY impress her, send her a card once or twice a week. If you put a little effort into it you can find reasonably well-done cards with a "friendship", "missing you" or "thinking of you" message for under a dollar - I hope she's worth that much to you! Write a short paragraph or two about something you did that you want to share with her. A real, handwritten, note from a genuine human is SO RARE these days that you'll stand head and shoulders above all the other guys she sees and talks to every day.)
Talk to her about what your physical relationship should be. If her previous B/F "used her" one of the best things you can do is let HER set the pace for what you do. Take your time with each step. First kisses are thrilling and nice - it will take a month or two to learn how to do it well with each other. I was a year older than you when I loved my first girlfriend. It lasted about 6 months until distance drove us apart. We never got beyond necking, but I'm grateful to this day (35 years later) for all that I learned from her. (Patty B. if you see this I hope you're well and happy! If my wife only knew how much she owes you . . . ).
Look at the very pleasureable non-coital things you can do - the currently trendy term is "outercourse". Think of them as a progression from holding hands to penis-in-vagina sex. Discuss with your G/F when these things should be introduced. These aren't so much a substitute for intercourse, but valuable skills you'll use in your future lovemaking. You're not really ready for intercourse until you are comfortable with each others' bodies and familiar with each others' orgasmic responses. You're probably at least 3 or 4 months away from that time.
Now for the answer to your original question - if her "experience" matters to you, you're probably not ready yet. Since her previous experience was negative, you need to make sure that you give her something very different. Treat her like a virgin anyway. When she's ready to envelope your erection with her vagina she'll let you know.