I understand your frustration, but please don't blame all dog owners. A lot of us are runners/cyclist ourselves and therefore are conscious of what are dog is doing at all times. We take our dog to an off-the-leash park in Baltimore where there are more runners that dogs. We make EVERY effort to pull our dog aside and OFF the trail when there is a runner or cyclist. Hardly ever do we get a thank you or even a glance for being courteous to runners or cyclists!
I am glad you weren't hurt, but if you are in a neighborhood, perhaps it is smart not to have your MP3 player up too loud. You noted you thought you were getting raped, so this should be a lesson to turn it down. You can hear someone running up behind you to cause harm, you could here a dog- mean or nice- running behind you, or you can even hear a car coming- whose driver may not be paying attention or speeding and could potentially run you over. It is an imperfect world and you have to be prepared for anything, anywhere. That is why I don't run with music, because I am being proactive about my well being. I am not saying don't run to music, just have it turned down a bit. Also, remember that you don't own the road, you share it.
With regards to the dog's owner only giving you a "sorry"... Personally, if my dog got away, I would try to see if you were ok, help you get up, and do whatever I could. However, many runners run away before you can say more than sorry because they are embarrassed or want to keep on pace. Please tell me what you would like to hear a dog owner say?