Hi there, confusedme (confusedyou?).
I don't doubt your lack of jealousy. I wasn't born with a jealousy unit installed either. In some ways, this feels almost unfair when hearing from others about their jealousy issues.
Looking at the timing of your situation, you had 9 years of together time with some open marriage stuff going on. In March you opened your marriage back up.
So in the last four months, you've:
Opened the marriage again
Developed feelings (C)
Self-identified as poly
Come out to the wife as poly
The wife has met someone in a poly relationship (J)
Lost your someone (C)
Found a new someone (A)
Lost the new someone (A)
Potentially had your testicles in a piece of uncomfortable hardware not intended for use with your testicles
Posted your story here
Wow. I'm tired just writing that--my nuts aren't in any duress. Seems like a lot of stuff going on in the latest 3.7% of your relationship with the wife. I'm not surprised she's coping poorly with jealousy when you sort of changed the plan (open marriage to poly). Both of you are going to need time to adjust to poly life.
So far it sounds like you're off to a better start, but part of what you get to work on is how to communicate with wifey and how to help her along her journey (in so much as you can). One thing that I've learned as a person who is personally functionally jealousy-illiterate is that we need to recognize that some things which are very important to someone dealing with jealousy will just slide right off our radar. While wifey learns about coping with jealousy, you might be well served doing the same so that you can pick up on details that might be important to her but invisible to the non-jealous. You might be making stuff harder on her not realizing that some of what you do can be triggers for jealousy.
As you get further down the poly road, things will get easier. Right now you're still comparatively new, bumps and bruises are to be expected.
Two new amors in four months? I'd be jealous of you, too. Don't kids these days take any time to say hello before imploding a relationship? *comically old people grumble*