KMC Forums - Any Dark Tower Fans here?

Really liked the dark tower series, thought they were a great way to end Stephen King's career by mixing characters from old stories to this one.
However, I was a bit confused about the ending and I wonder if anyone can explain it to me in simpler terms.

FYI--WARNING: SPOILERS BELOW!!

1/ At the end of book 7, roland is transported back by ka to the start of book 1, with one major difference: wher he was missing his horn at the start of book 1, by the end of book 7 he had regained it, after he had picked it up after Jericho Hill. Does this mean that history in total has changed, and despite chasing Walter again, the tower is still safe and no longer in any danger from the breakers and the crimson king? Or does it mean that the quest is repeating itself as it did through the series (i.e. meeting eddie and susannah and jack mort in book 2, killing shardik in book 3, beating the wolves in book 5, etc)? Or does he have to go to the tower by himself this time? As well as starting the quest again, has time reset to the age he was when he first started the quest, or is time going on, so if it takes him a year to get to the tower, and then throws him back to the start, will he be 1 year older each time, or the same age as the first time?

2/ If so, what happens to eddie, susannah and jake? Is their part finished, or does it happen again? Does time now run forward that the tower has been saved, or as with starting again, is the tower back to square one, and continuing to fall again at the hands of the breakers and the crimson king?

If anyone could throw some light on these questions if possible and drag me out of todash I would appreciate it. Thanks again.