Dad had an affair

As the title states, i recently found out my father has had an affair. He has just explained everything to me and come clean about why it happened and he has held his hands up and understands it may take time and accepts i may never forgive etc. I had my say and got alot off my chest as i was angry, we argued and talked but then it all came to a sudden stop when he said "i dont want to talk about it anymore, i've owned up to it thats it." Then walked off.I'm confused to say the least, I couldn't quite believe he just walked away as i wasn't finished. I don't know how to react as i feel like thats a statement in itself as if he's not bothered about what i think and whats done is done. My other 2 siblings are younger and seem to have accepted it all, as with my mother they are sorting it out together with him but i feel left out the loop and quite frankly i'm in disbelief...This obviously is very soon and i still have a long way to go but we don't have a close relationship as it is and i feel this is going to cause an even bigger gap to which i'm worried might cause me to move out.Anyway i just wanted to vent my thoughts, would appreciate any advice :) via /r/Parenting http://ift.tt/2owWW3k