Did you tell her you'd already spoken to your friend about this?
Because if she made you sleep on the couch,it sounds like she was both hurt and offended
.Perhaps you are moving a bit too fast on this.When swinging first becomes a thought in your head, it can take many moons to become a reality.For me{female}, at first I went through the whole sanctity of marriage issue and how can it be okay to actually sleep with another person, yada yada...but I still wanted to do it
...so, I had to wrestle 
with that for awhile and come to terms within myself about things.Joining the boards has helped tremendously.I don't know about other women or men on here, but I think in the beginning, you do question a lot of things until you become more comfortable and really open your mind... 
Take your time,it could be years before she's ready...but if it's meant to be...it will happen 
.However, do not push her...you will lose out on any chance you might have had if you do 
.Apologize to her for talking to your friend first...you should've talked to her from the get go...before you even told your friend you wouldn't mind swapping,you should've told her about it.And then let her think about it awhile before even telling your friend you did indeed like the idea of swapping.
Buy her some flowers and take her somewhere nice and really work on making up for your lapse in judgement... 
we all make mistakes ...Good Luck in the future