One of the best Taiwanese drama out there. Re-watching this from time to time. It's so good. I mean, Meteor Garden was the one that started me on T-dramas...but this drama is a good heartfelt one. And believe me when I say, this original drama is better than its Korean remake. Trust me, stick to this version.

My review when I watched in Oct 2016:
Finished watching this amazing Taiwanese drama yesterday. It was a 13 episode drama but it is about 1 hour and 30 mins long per episode. I think its broken down differently in different sites. Just check it out.
Anyway, my verdict is HIGHLY RECOMMENDED. It is not a perfect show but it definitely captured my emotions. I was definitely entertained. Its a good mix of emotions such as comedy, drama, heartbreaking, warmth and comfy. It was a great drama. The lead actors are a delight to watch as well. Don't know where to start praising this drama. I heard that it won a lot of awards in Taiwan. And the very fact that it was remade in Korea as "The Time that we were not In Love" means that it has a good story plot for another country to remake it.
First off, the lead actor, Bolin Chen and the lead actress, Ariel Lin, did a great performance to convince you that they are indeed bestfriends who are hiding secret longing from one another. It was very heartbreaking to watch up until episode 12 I think. It makes you think like "Are they ever gonna be together?". But of course, we know on the onset that they will be. So just be patient.
The one thing I just did not like was the very first episode or atleast half of it, its kinda boring, with the monkey or gorilla something that was being chased by Cheng You Ching (Ariel Lin) at the beginning. I know this signifies "time" because she was problematic as hell for being 30 and mature. But it was kinda off putting for me. Like, you can be happy at any age please. Like there is a saying that "life begins at 40" right. Just look at Li DaRen's (Bolin Chen) mom, who got married who know how old she was to Uncle Bai (the bestfriend of Li DaRen's mom). Anyway, maybe the gorilla thing just pissed me off. Haha. Just my two cents. But I promise you, just get pass that, you will enjoy the whole drama.
As for Li DaRen, I like how he is so gentle and kind. A perfect match for our arrogant Cheng You Ching. He is always there for her, even if he has a girlfriend. And never outsteps his boundaries as a male friend, especially when You Ching had a boyfriend/fiancee in Ding Li Wei.
As for Ding Li Wei, I am not sure. I think that he was really an ass before when him and You Ching broke up 5 years ago, but this time, he really has changed. But he was kinda "caught in the act" that night with his assistant coming out of the shower in a towel. I feel that he was kinda set up by his assistant. It was not really explained further. Since Li Wei had a history of cheating with You Ching, so its unforgivable to even see a woman, much more, a barely dressed woman in a towel in his apartment. So that is that. You Ching was about to break off her engagement to him anyway. So it just gave her all the more reason to break up.
As for the "lessons" that You Ching kept on imparting per episode, the lessons for the "mature woman", it is nice and left a mark. They are all true. Any female could learn from them.
And finally, the part where they are about to become a "couple", at the IKEA showroom, on You Ching's birthday, it was so cute. Like You Ching knows that DaRen is courting her, so she then calls and consults her "bestfriend" over the phone with is DaRen also...Then after that, things just went into their "proper places" as it should be. Like being with each other even if flying back and forth between Singapore and Taiwan just to see each other for 2 hours at the least. The marriage proposal after deciding to finally be together in Taiwan after a coin toss between choosing from Singapore and Taiwan to settle. The wedding, of course. The awkward way that they kiss at first. The acceptance of the mom of DaRen with You Ching as official part of the family. The ties created between You Ching's family and DaRen's family, that they can visit each other anytime. And finally, the awkward honeymoon in Singapore. Then the perfect ending that points out that all relationships are not perfect after all. How DaRen persuades pissed of You Ching to go home after coming back to her parent's house with a luggage since they fought.
Soundtrack is pretty good. Matched the cozy and warm feeling while watching this show.
Obviously, I liked this drama a lot. Will repeat it again sometime soon. Or watch the remake (The time we were not in love), which I am not sure will measure up to this.