I truly find it utterly fascinating when westerners make comments about eastern characters based on a completely different set of values and morals as though the character was of the same background as them.
These characters are JAPANESE people. Toru is NOT being a coward (by Japanese standards) nor is he being completely dense. You cannot push your views on characters written by people who fundamentally think differently than you do.
The Japanese are historically more reserved than their western counterparts.
And, finally, do you WANT the series to end so quickly? If he weren't like this and realized she was a girl and they got together it would be over. End of story. Good bye.
Based on all other stories that I have read based on the same setting I can say that the story will, beyond the shadow of a doubt, end when he gets together with someone. (A new story by a different name *may* start after, but that's completely different and utterly optional).