So here's the skinny...

Me early 30's, working professional - Her mid 20's, grad student with an internship

I've been dating, well let's say "talking", to a girl for the past two months and we live across the country from one another. We have shared 3 different trips together over those two months and have had a complete blast on each trip. The final trip was here in my hometown and we spent time together and with my friends showing her some details of my life. We had an absolutely awesome time with the trip ending with a comment of how crazy she is about me while cuddling in bed. We talk or text daily and I've, for the most part, been able to recognize her normal levels of interaction. About a week ago things have changed a bit.
A comment was made, in a very lighthearted and joking light, about how she has anywhere from 1-5 years left of school and moving here was potentially way down the line. Again, this was in a very lighthearted manner and no serious talks of moving have ever been brought up. But, what this comment did start was a feeling from my end about being realistic and whether this should be pursued any further or if we should cut ties and call it off. This apparently started to show in text messages as I was being "distant" in her words. She asked if I was OK and why I was being distant later on in the day. I responded with the fact that 5 years is a long time to date long distance and maybe we should talk about where this is heading.
Now my intention wasn't meant to stir up an "All or Nothing" conversation - more along the lines of a general direction of things... are we on the same page - but, it did in fact lead to a very uncomfortable conversation and I had to do some serious back pedaling to just keep things from completely falling apart. In her eyes, it went from easy and carefree to "pressure." As though things had to be planned out with an ultimate goal on the horizon. It went from her concern of me being distant to a complete 180 and her not knowing what she is feeling about all of this and "maybe we're at different stages in our lives."
So I'll admit. I do feel quite a bit for this person. Enough to spend time, money and emotions on someone who lives very far away. I do not want to lose the opportunity at something great because I came on too strong. Now we do have another trip that we are talking about planning but I'm trying to get back to where we were a week ago... which seemed to change in literally a 30 minute period. Prior to that uncomfortable conversation, I would receive text message early in the morning, random picture messages of her doing daily stuff, messages about her missing me to where we are today - almost 1pm, no text, no I'm missing you, no pic messages... this has been going on for days now. Now we are still talking, talking about another trip. Our conversation last night was almost an hour long and very casual. I brought up a trip - she confirmed it to be a good idea. I said I missed her and she confirmed the same... I'm doing all the initiating now. I can sense a change in the overall dynamic of things. I need to get back to where things were. I have a feeling that she is about to distance herself further until it is completely gone.
My thoughts are:
*give her some space - ease up on the my initiating of the texting and can't wait to see you comments to see how she responds. Create that fear of loss feeling so she'll turn things around.
*I have some gifts for her that I planned on sending (very specific, thought provoking, sentimental gifts) but I'm hesitant because I'm afraid they will not be received as well as they would have a week ago. Just some stuff to let her know I care.
*Possibly cutting things off - telling her that a trip is not a good idea with the way things currently stand. (taking the approach of I'm just fine without you in my life and creating that "want what you can't have" impression in her mind)

Bottom line is... I like this girl. She has many qualities I find attractive. Normally my path would be to tell her exactly what's on my mind but the small glimpse of that has pushed her away. I'm not trying to play games, I have no ill intentions. I just want the opportunity to date this girl for a while and see if this has any legs.

I going to go against your gut feeling. I don't think that you should give her space. I think that you should give her an opportunity to express herself. Based on the entire story, I still don't know or understand where she stands. I suggest you lay out your cards with her and see where she stands exactly. Only give her space if she asked for it. Until then, you two seem to have so much misunderstanding. Both of you seem to be holding back from saying what you honestly feel. Until you can be honest with each other, you can't move forward.

So go call her and clear the air before you decide on what to do next.

Yes you both need to be honest and direct on where you think this relationship is going. Can you both afford monthly trips to each others homes ? Or will this be months and months with no phsycial meetings, just on line

Thus the trouble with long distance, it would be different if you were together for a long time and one of you had to be gone for a year or so, that is hard enough. But here you really hardly know each other. But with long distance, the final issue will be at some point it either ends, or it has to be that one party will move to where the other party lives ( or both move 1/2 way)

So she can't move because of school ? No schools in your area
Can you move ?

That has to happen to one of you at some point if the relationship grows,

Dude, you are clearly awesome... the gifts say it all. You are in a mutual emotional relationship with this person, so just get on with it. Never let the complexity of long distance communications damage your obvious love and affection for each other. Send her the gifts (not all at once, think about it and pick your time same as you did when you chose the presents, make them count), and go for it. Seduce her with your affections - be cool, but intense, try not to be a stalker, just do your best ;-)
It may not all work out, but if you get it right (which you will) she'll love the attention, and worst case, she'll remember you forever.

The phone calls can be difficult though... it's easy to get into a routine, and have nothing to say to each other, so make sure you take a stand and manage that. Avoid arranging to phone at the same time every day. Avoid arranging to phone every day. Make the point in a light hearted manner - tell her you'll be more entertaining if you speak weekly - it'll take the pressure off her too and she will appreciate it. But remember to call her between the scheduled calls, just because you miss her and you can't wait that long to hear her voice.

And when you guys meet up, make sure you have more things planned to do than you actually have time for... stuff you usually do, stuff you've never done before and stuff with friends.

You guys will have the best relationship and love each other even more because of it... bottom line, you get to spend the time together that you want to spend together, the normal day to day kak that everyone has to deal with you can handle by yourself.

When she finishes school, just don't stop with all the fun stuff. It's easy to do, but you don't have to ;-)

Tell her exactly how you feel about her.
Make sure you understand exactly how she feels about you.

Two months into a relationship is too soon to be talking moving in. Especially when it is a long distance relationship.

Stay straight up and totally honest. Start learning now how to communicate with her to the point you can talk about anything without getting angry or hurt or apprehensive.

The best way to let someone know how you feel is to tell them.
The best way to find out how they feel is to ask.

Communication , honesty, and trust must be the basis of a relationship if it is to flourish and bloom.

I wish you well.