
blabla100:
unless Tong hua comes out and explain these things herself we will probably never know her real intentions,
I think if one reads the novel carefully and reads Tong Hua's numerous interviews around it, one does get a pretty good idea of her intentions/opinions on the individual characters' choices and ending.
Tong Hua - true to the writer that she is - is very precise with her use of words. Like Kokuto pointed out, she never said that LYF was a happy ending, merely that it wasn't tragic. Not only that, but it wasn't a tragic ending because the characters all got what they wanted/aimed for. What she left unsaid was whether what they thought they wanted would be satisfying in the long run. Like the idiom you referenced: "Be careful what you wish for or you just might get it" (and realise too late, that it's not what you wanted after all). One of the main themes of the novel is that we can't get everything that we want in life, and settling for "good enough" is what most characters end up doing.

blabla100:
I personally wanted to see how these characters fight their fears, go against the flow, but instead they all reached a point where they got what they wanted, but gain nothing worth living for.
This novel is frustrating because we have certain expectations when we read romance novels (in which LYF is predominantly); we expect a happy ending, and we expect characters to fight for love and triumph. Instead, Tong Hua chose to write about traumatized characters and the "imperfect" choices that they made due to their trauma. To make it worse, she also didn't let our heroine achieve much growth or breakthrough for the entire novel.

blabla100:
I wish she would have done more, go against everyone and everything, XL would probably still rejected her, but be ambitious for once. She kept saying her biggest fear is to be abandoned by the people she loves, but all I could see is her giving up on herself for the people that loved her. Couldn't she be selfish for once? She wanted someone to put her first, but she herself wasn't able to do that. Yes, her romance with XL would have been doomed, but at least I'd have seen her becoming true to herself.
The above is also why I find the character of Xiao Yao to be incredibly frustrating. I didn't find her to be likable or compelling - just quite pitiful. However, my reference tends to run towards the Ah Heng and Ruo Xi of the world.
Ruo Xi actually made a decisive rational decision, whereas Xiao Yao always hedged her bet. She didn't even admit to her feelings for Xiang Liu. If she had come out and said that she loves Xiang Liu, but because of their doomed ending she chose Jing, then worked to cut ties with Xiang Liu (getting rid of the Lovers Bugs etc.), I probably wouldn't have been so frustrated with her. But I guess, Tong Hua had already written one Ruo Xi and she didn't want to write another one.

blabla100:
Oh yes, I know Jingers belive XY and Jing got their happy ending, but let's be serious, none of the characters achieved their goals without losing love on the road, should I actually belive Tonghua made an exception for them?
Even Tong Hua didn't say that it was a happy ending. It's probably a happy ending for Jing; out of the four main characters, Jing is probably the only one who gets the happy ending. Xiao Yao, on the other hand, her ending is rather tragic, IMO. She got exactly what she wanted - a companion who would never leave her, because by the end of the story Jing had become completely dependent on her and couldn't leave her even if he wanted to. Objectively speaking, is this actually a positive thing? Subjectively speaking, maybe if she had never met Xiang Liu, then ending up with Jing as a companion would have been enough. Unfortunately, she met Xiang Liu and experienced the difference between a companion and a soulmate. The eternal yearning and regrets are the price for her lack of courage. It's better to regret making a wrong choice than regret never having the courage to make a choice at all. At least with the first, you have been true to yourself, rather than deal with the regret of what might have been.