Tut tut. Option two methinks. It is only fair that you remove yourself from the equation.
Yes, you are completely selfish but I cannot condemn or slate you for the way you feel, it's not your fault, it's nobody's fault really. Unfortunately sometimes the spark just fades, especially if you are both not actively working at your relationship. It was absolutely wrong for you to start fanatsising about the sister though, what makes you think she is even interested?! It is human nature to want what we can't have but unfortunately the grass is not always greener, as I am sure you have heard a gadzillion times before.
What you have done though is ruined whatever relationship the two sisters shared, not to mention the fact that you have hurt Amy deeply - she deserves better and if you agree then you should walk away from her, just let her be. If you are not attracted to her anymore and don't have any feelings of a romantic nature then stop kidding yourself as well as her. I don't like your 'if I can't have Anita then oh well, guess I will make do with Amy' mentality - it's shocking! You need to stop stringing Amy along, at the same time you musn't just settle for somebody out of guilt or pity, you will only regret it and spend many years wondering 'what if?'. Do not confine yourself to an unsatisfactory and unhappy relationship. For the sake of the interests of all those concerned in this triangle, forget both sisters is what I suggest. Good luck dude.
[SIGPIC][/SIGPIC]
Love is like a merry-go-round: you get all dizzy, and then you feel sick!