It's a pity for Kaew broke up with BOR, but I don't think it's Kaew's mistake. She had no more choice from beginning. Now after six years, when the bor's sister came out of prison,she became more crazy. I can't imagine if Kaew still with BOR, what his sister will do to her, maybe she will kill her.LOL, you just might be right about that. I think that one of the biggest obstacle for Kaew and Bor and for Kong and Piwit is the mom. It seems the kids are trying to move on but the mom can't let go of the past and constantly reminds them of it. Totally undersandable but there must be a point when we all must let go in order to live a meaningful life. If the mom does die, I think it would be b/c of her uncurable illness.
For me the perfect ending would be:
-Awn is pregnant but it's Pipat's baby and Pipat being the manwhore that he is accepts no responsibility
-Pipat gets shot in the nuts by Bor's sister and is impotent in that department, of course this drives him crazy b/c he feels less of a man
-Bor's sister sees the light and seeks forgiveness from Kaew's family
-Kaew's mom is free from her anger and allows her children to follow their hearts
-Piwit and Kong end up together, Pueng and Tunwa are really good friends, Nuithi tries to woo Pueng but she rejects him
-Bor begs Kaew for forgiveness(b/c of the r-scene from the spoiler), he goes after her but she runs from him and her feelings, he stops bothering her b/c he's come to a realization that maybe although she will be the only person he will ever love, just maybe they weren't destined to be be togehter. At the end, it's Kaew who realizes that she can't live without him. She had let the love of her life walk out of her life and she's not going to make the same mistake this time around b/c she is free to love him openly now so it is Kaew that goes after Bor and of course he accepts her with open arms (sometimes I want to see the n'ek go after the p'ek. Also, I think it would be fitting for this lakorn b/c she broke it off with him the first time around, it would be nice for Bor to see that she loves and wants him just as much as he loves and wants her.
so if a happy ending,the key point is his sister.