a] for something which is happened in past
b] Something you are facing in present
c] Something you dreamed and realized that it will not happen.. broken dream..
I think a] happens when you can't dream well.. if you can dream well, then you will come out of past pains.. but then that may lead to c.. and thus vicious cycle...
I think c] happens when you are really really dreamy and then you enjoy all the dream.. But then you feel pain when you realize that dream is not going to be true.. but then if you have high re-constructive power, you will see new dream... quite difficult, but you can.. or you need to live in present then nothing will affect you related to future in present..but then it can lead to b.. and then vicious cycle... So reconstruction can be ultimate solution..
And for b] , you need to depend upon past good things or future hope.. again both of the things lead to either a or c and hence vicious cycle..or you can face the pain in present...
So ultimately two solutions..
a] Reconstruct... accept no reality exist.. or better to say whatever you construct is reality.. so you construct your happy world.. and this construction need to be highly flexible and adaptive..
b] or Live in present and accept the pains which are in present.. and face then.. but then how to face them.. that i don't know.. i always go for reconstruction..
I think there is nothing like present.. it is just awareness of past or future... so b does not exist,, ans thus reconstruction can be the ultimate solution..