Why Did They Cancel Invasion?

I am so mad! ABC has cancelled one of my favorite shows. Invasion. Couldn't they at least give us a few more episodes to finish the storyline?  I always wondered how the show could keep going on with the current plot. It always felt like a mini-series. But to end it on a cliffhanger, is just plain mean and stupid. It really isn't fair to cancel a show of this style, in this manner. It's like only giving us half a book. The Fox Network did the same thing with Point Pleasant last year. Not to mention they didn't show it on a consistent basis, just as with Point Pleasant. If you are going to commit to airing a nighttime soap opera, at least commit to resolving the main storyline before cancelling it. Why will any of us continue to watch new series if we are going to be continually left in the lurch? Sometimes a show takes a while to build an audience, especially one that requires you to know what went on in the beginning. You have to give people time to catch up with reruns. I really didn't catch on to Desperate Housewives until the first season was almost over. I had to see the earlier episodes first. Please ABC, at least finish the storyline on DVD. It would make a great boxed set. The show was far superior to Taken, and I am sure would sell well.