Rainbow Dash was many things at that point in her life, the least of which was clueless. No, that distinction went to her closest friends. I suppose you could say the same about myself as well, but at least I had an excuse.
It's not as though the other ponies could be faulted, either. Rainbow Dash held them at a distance. In a way, she always did, but with the way things had gone since the Gala, Rainbow was becoming more and more of a stranger. It would have been a very sad thing, hadn't she still continued to be a loyal pegasus who would do anything for her dear companions in an instant.
I think we all go through phases where we get caught up in our own private lives, be they epic or underwhelming. Rainbow's life had certainly got adventurous, and it's not as though she lost sight of her priorities. There's just so little time that a pegasus can spend doing the things that are most important.
At least, where Rainbow is concerned, she didn't risk losing her friends or anything terrible like that. However, she did risk losing her sanity. She was soon to discover that the price for living life constantly on the go is that the place you have to come home to reacts like a nasty rash.
Oh so itchy...