When Things Fall Apart

It's the classic scenerio: Boy meets girl, girl meets boy. They hit it off, both laughing at the same jokes, both loving each other's casual company. But then as time passes, changes occur. They can be brought on by the outside elements-- a new job, new opportunity, new people-- or it could also be an inner change-- new interests, new beliefs. Changes are natural, like it or not. We can't avoid them. And so when these changes occur within relationships, you deal with it by choosing one of these two options: 1) Embrace the changes that occur within your significant other, as difficult as that may be, or 2) Give up on them because of the belief that the changes are too severe; what made the relationship great before is now lost forever. Neither option is necessarily the absolute correct option, although option 2 could be classified as a "last resort" option. It really depends on the situation. But this isn't about romantic relationships. This is about friendships. Do these "options" still apply when character traits alter, when persons metamorphose?
I am in the midst of deciding between option 1 and option 2 in a very important friendship in my life. The both of us have been through changes recently, inward and outward, which have deeply affected our lives and lifestyles. Personally, I just got done with two and half months of studying abroad. I experienced so much-- without my friend by my side-- that change absolutely occurred. I was surrounded by new friends and created memories that I deeply cherish and think about often. It was hard being away from my friend for that period of time, but returning to the States and picking up our relationship from where we left off was ultimately impossible. Neither of us was the same person we were two and a half months previously. She herself had been through a fun and exciting change, but I wasn't there for it, to be there with her and rejoice in this new development. It was a rude awakening, as if I had been asleep, and woken up to find a completely different friend. Again, the changes that we went through individually are not bad. On the contrary, they are the best kind of changes, that broaden the mind and make life more beautiful.
However, I don't know where to go from here. I have tried embracing the changes she went through, but have discovered that the new factor in her life seems to be overshadowing the friendship we used to share. I feel more and more like things are being rearranged, and there is no longer room for me on her list of priorities and interests. So I'm surveying option 2... But it seems a little too harsh. After investing in her, I am not just going to give up on her all-together, even if it feels like she's giving up on me. Our relationship certainly isn't what it used to be, but we have a safety net of good memories and shared interests that seem to break our fall.
So here is option 3: Lay off a little, rather than throw in the towel all-together. Continue to embrace the changes, but don't beat the self up about such things. If nerves are tested, just back off, take a breather, and never forget that sacrificing your own individuality is an unwise decision within any relationship.
But what it really comes down to is this simple fact: friendships are a very sacred gift. If you think of them as a gift from above, as Hallmark as that sounds, you will think more than twice about simply discarding them because interest in that gift has altered or dimmed.