DW is pretty motivated by titles as well, so I understand that. When she starts lamenting situations about titles at work, I ask how much more XXXX pays vs. YYYY and if there's more benefit involved. Usually, the answer is no, and usually it's just a change or step increase in responsibility. When it's framed that way, she's pretty happy to keep whatever title she has and just angle for more money.
My advice - and my action in this case, if it were me - would be to swallow your pride. As others said, in 10 years when you're retired, it won't matter one bit.
"So we beat to our own drummer in the sun;
We ask for nobody's permission to run.
I just wanna live in a world like that;
Now I'm gonna live in a world like that!" - World Like That, O.A.R.