If someone you swings with starts to have feelings for you, first you certainly would tell your spouse/partner! You must always maintain an open, honest communication within your relationship. I would not only tell this "too attached" swinging partner that it's inappropriate, I would also tell them that you do not share those feelings, that you have told your spouse/partner and that you will no longer be swinging with them. You may want to stay friends but I would advise you to place distance between you and them. This kind of situation happens much more often than many of us may realize. Those not into polyamory do not accept this while swinging but there are many polyamorous swingers. For you in this situation, simply move on.
"Tossing a salad" sexually speaking, is the act of licking the anal opening. Some also consider this to be a form of "rimming"