All you need is love?

Ok, I really want to agree with Shakespeare here. Maybe I just don't completely understand Sonnet 116, but I can't completely buy into Shakespeare's idea of love."Love is not love/Which alters when alteration finds,/Or with the remover to remove." The idea of a pure and true love is great. I will even go as far as to say that I believe in this kind of love; a love so pure that nobody can impede or destroy it. What I don't understand, or possibly even agree with, is that if a love is breakable, it is not true love. In my personal experiences I have seen people that truly love each other and then eventually cheat, lie, and destroy their love. I do not think this means that the love they once shared was impure. Just to clarify, this is where I am a bit uncertain as to how Shakespeare defines love. Is Shakespeare Suggesting that a love that has been broken was never love, or is Shakespeare suggesting that a love that has been broken was once true love, but now cannot be considered true love because of its imperfection? The line, "O, no, it is an ever fixed mark...never to be shaken...", leads me to think that Shakespeare believes that love was never true love if at any time it was in doubt or shaken. For this reason I don't see eye-to-eye with Shakespeare's definition of love. I think that, just like the seasons Shakespeare is so fond of, love has many phases. Sometimes love withers and dies and sometimes it lasts forever. If a love you once had withers and dies, I truly believe that it could have once been true love. Love is tricky and Tennyson said it best, "I hold it true, whate'er befall; I feel it, when I sorrow most; 'Tis better to have loved and lost Than never to have loved at all."