I don't know about 7 days of circling the alter on sukkot. But on the last day of sukkot the alter is circled 7 times that is meant to resemble the 7 circles around the walls of Jericho. And some say that the 7 circles on a wedding is to break the wall between the bride and the groom. So that may be the link between all three. All link back to breaking the walls of "Jericho".
https://en.m.wikipedia.org/wiki/Hakafot Best source other that random sites is wikipedia :)