I'd say part of it is friendvy - when you become so envious of your friends life that you literally began to despise them and question their value. Yet, you shouldn't let your covetousness of their life ruin your relationship. Instead, congratulate them and continue to support them throughout their successes. Yours are coming someday.
Sometimes friendships fall apart because of distance. When one friend moves across the state or country, it's hard to see them as often as you'd like. Especially when finances become an issue. To me, this is one of the worst ways a friendship can end. Someone dropping you simply because they moved away is basically a representation of what your friendship was to them - convenient.
Though these are the most comment of reasons relationships fail, in my personal experience, I blame a lot of broken friendship on clearer vision. That is, I opened my eyes and realized what type of people these 'friends' are - and most importantly, what type of person I am.
In the past year, I lost two friends via clarity. These were friends I pictured of having around in my life forever. These were friends I wanted in my wedding, to have my children refer to as "Auntie" or "Uncle", to go on fabulous vacations to Europe with, and to grow old laughing with. In the last 3 months alone, I realized I will never be able to live out those dreams with these people... and here's why - these are selfish, genuinely unhappy people.
I had a friend who I would have done - and did - anything for. I traveled to this person at their beckon call any time they needed me. I took the time to listen to their problems whenever they had any, even those times I was battling my own, in hopes that they would be there for me should I need them. However, this was a one sided relationship. I learned this quickly after shelling out well over $1,000 for a visit and a concert that never happened. A concert that I will never get to see now. A trip that I will never get to take now. Apparently my friendship wasn't comparable in value to another relationship they were invested in at that time, and someone else's needs were chosen over mine.
Another friendship fell apart when a friend moved across the country for an internship. Though the internship left something to be desired, this friend felt it was their star calling, and thus everyone should have been on the same level as them. I was proud of them, but felt my wants and needs didn't match up to theirs. Eventually, they started making me feel bad about myself; that I didn't drop everything to move, or that I was in the wrong, working a 9-5 and going out with friends on the weekends.
It took some time for me to realize that real friends aren't like that. Real friends don't leave their friends stranded across the country because of some guy. Real friends don't make you feel bad because you're living your life differently than they are living theirs. Real friends do the opposite.
In fact, because I didn't get to go to said concert, my other friends planned a night of movies, music, and wine for me. We laughed, cried, and drank until the sun came up. They have never once made me feel bad for the way I live my life, or for raging during the weekend. Nine times out of 10 they are raging with me. Those are the people you keep around. Stop and smell the roses. Take the time to evaluate your relationships. If someone is bringing you down, regardless of how they once made you feel... drop the weight. After all, a friendship that can end, never truly began.
