I was trying to write to you before, but I let go so she could get back in to continue with you.
I want to comment too because I've done dream interpretation for 35 years in private practice as a Marriage & Family therapist (now in Florida). I agree with Debra in general about dreams, and would add that it's important first to 1. know what she remembers of the dreams and 2. to figure out thru asking questions about dream content what level of interpretation would be most useful to the dreamer to explore.
1. Even without knowing anything more about the content of any particular dream, you could ask her (substitution method) how the dream would have felt different if instead of X, whose name she called out, the main character had been Y, another one of her FSNs (Frequently Spoken Names). That'll get you closer to the meaning of the name she did use very quickly. For example, You could substitute for the disgusting guy either somebody she likes at work or somebody she's totally neutral about. The differences she brings up in how the dream would FEEL, a vague term on purpose. You can make it even more generic, like "What might you SENSE as different?" or "If you were dreaming in colors, how would the colors be different?" In each case you can pursue the meanings of her answers, and remember every word she says as perhaps a hint of what sort of a dream she was having. If she says "But I don't even remember what kind of a dream, or what color I dreamed" you can still say "But if you would make up a strange dream NOW about the neutral guy or positive guy how might it be different (colored) from another dream made up about Disgusting-guy?" Anything she says, no matter how unrelated to your question, could be a hint about what she was dreaming about. Most people don't remember dreams most of the time, so she's not unusual.
2. You've got to realize that you might be intruding on her sacred inner space when you try to interpret her dream, and you're also likely to be biased in any interpreting you do. In fact your use of the 2 men fantasy might have "tipped her off" unconsciously that it wasn't safe to say any names out loud, so her unconscious mind shut off the microphone. Debra's idea that the dreams could cover different things besides sex is a very good one. It's men who normally have much more sexual overtones in relationship dreams than women do, so we men could easily assume that she's dreaming about sex too. Question #1 above could show you pretty quickly whether the theme is sexual or something else. She.s almost certainly not conscious about what she's unconsciously concerned with, and she's very devoted to staying in love with you.
Would you feel threatened if, as Debra suggested, she has "unfinished business" with exlovers? If you want to check that idea, you could ask her the same questions in#1, but use 2 different ex-lovers. You could find out more about how each of them affects her by her answers. But you are fishing in dangerously uncomfortable waters, and you might find out stuff you will wish you hadn't found.
It may be unwise to probe beyond what she's told you about ex-lovers, esp if she doesn't want to think about them herself. I know I never do it, and my wife of 25 years is careful not to tell me anything that could hurt me by comparison. She's been interpreting her dreams for 36 years and hundreds of other people's dreams since 1993. I haven't even mentioned your wife's dreams to her. If she thought I wanted her ideas she'd stop and might well have different intuitions than I do.
Another common meaning of dreaming about another man is that the dream-man represents how she's feeling about you lately. If it's Disgusting, then she's been repulsed about some aspect of you, The peculiar nature of each ex-lover could represent those aspects of you that she was particularly attracted to lately. Or if it was a Freudian interpreting those dreams, she/he might say your wife is wishing you had more of what that ex-lover had--"wish fulfillment."
I still haven't tried to interpret her sexual response in conjunction with those dreams, and Debra may be right that her sex drive is peaking and she's looking for something MORE, but probably NOT a threesome as you've assumed. If she's really neutral about your 3 some imagery, you could be off-base. If she's actually turned off, but goes along with your supposed fantasy, then perhaps your marriage has the potential of entering new realms of feeling, new interests, and even new ways to experience your sexuality together. Perhaps a marriage enrichment weekend would jumpstart some new growth. It sounds like she doesn't want to lead you, perhaps because that was not a woman's role in her upbringing. But she could actually have some untended shoots in her own being that need to push up thru that old-ingrained prohibition. If she starts becoming more of her true potential self, you could have a new marriage to a fascinating woman you never knew existed!
Please give Debra her Accept for her excellent work. And if you want me to respond more, please put up a new question and frequent that it be for me only. I've given you a lot of different avenues to pursue here, as Debra did too. So you're getting much more than your money's worth already. You came to the right place.