If you want honest advice I think I have a couple things to opine. Take it with a grain of salt, from a guy whos in a happy non-feeder/feedee in-person relationship for what its worth:
- Its awesome that you found that and I would deeply encourage you to continue it for as long as possible youve really struck gold brother
- You should meet up with her ASAP. 600 miles is a lot but thats still a days drive, albeit a full days drive. Well worth it and neccesary imo to get a feel for each other in person. 99% chance you get on well and its a worthwhile experience and on the small chance you dont for some reason better to know sooner rather than later. Again, I stress this is a very small chance. If you get on well online for such extended periods that will almost certainly translate to irl, but no matter the outcome its worth it to take the first oppurtinitu and Id encourage you to start talking about it soon if youre both in this phase of long term thinking
- Purely online relationships in the long term are unsustainable. Youre in a honeymoon phase rn and thats ok and good, but I would maybe plan for somehow you two to meet in the middle in some way to actually live together or at least mear each other at some point. This doesnt need to be now, you can wait for major openings/oppurtunities (graduation, one of you finishes a job, etc), but I would be thinking about it at some point in 1-2 years.
Best of luck and congrats on your gf!