When can Eddie tell her who Barry is?
When he asks her to marry him?
When he puts an engagement ring on her finger?
When she says I do during the ceremony?
Oh boy.
What if Iris is not related to Eobard?
What if Iris is beaver damming (girl version of cock block.) the reverse Flash's heredity?
What if instead of being erased from History, from having a new ancestor, the wrong ancestor, Eobard Thawne becomes some what, a little bit black?
Obviously Wells is Wells, and Wells because it is a disguise and not what Eobard really looks like, is not going to change pigment as Eobards personal time line hickups, but when Thawne takes that mask off, he could see a very different face under there.
Hmmm.
Or has a lot of what he's been there for in the past has been (just enough) to make sure that Eddie and Iris did hook up, because she is his great great... great gammy, and it is that sexy Barry Allen who who was trying to paradox the Thawne line out of out his existence?
Here's the problem.
The engagement ring is half way down her finger and Eddie is already yelping "BARRYISTHEFLASH!"
"WTF?"
"Barry... Allen... Is.. The... Flash."
"What? This is hardly the time... Did you find out 5 minutes ago or, do ####? ####? What?"
"I wasn't allowed to tell you until we were married."
"Wasn't allowed?"
"Your father said..."
"MY FATHER?!"
"Yes, your father - "
"MY FATHER!! The only reason you asked me to marry you is because you wanted to tell me that Barry was the Flash you weak spineless son of a bitch!? Not because you love me, not because you want to spend your life with me but because you are afraid of my father you weak gutless ballless weasel! Barry is the Flash? THAT'S what all this #### has been about? OH for ####s sake!? ...How long have you been lying to me? Months? Sweet Christmas! Edward Thawne! I never want to see you again in my life!!"
"Eddie is not short for Edward..."
"I said #### off!"
...
Bridezilla interrupted.