Oh, how I can relate to this situation. It bears a lot of resemblance to when my ex-h first got a gf, 10 years ago.
We'd been together 20 years and raised 3 kids to teenagerhood (they were about 10-15yrs old at that point). Our relationship felt strong enough to open it, as we'd had more time for being together because the kids were more independent.
So... anyway, we met this woman who was supposed to be our unicorn (hot bi babe), but she turned out to not be into me, just into him (not bi after all, just bi-curious).
He was overcome by new relationship energy (NRE) and wanted a V. I didnt think she'd earned that status. Also I didn't understand his feelings of love for her were NRE, and felt he was more into her than into me. Despite our history and good sex life, I felt pushed aside. When he told me he wanted to move her in and make her a 2nd wife (after like, 3 dates), that they were soul mates, I made them break it off. It all felt too Mormon-like to me. He wasn't cool with me seeing other men then, just women (I'm bisexual).
Anyway! Enough about me.
What's this about your sex with her having to be slow and not wild because you're well endowed? I don't get that. Does it hurt her when you penetrate her too deeply? Some men with big cocks wear a donut shaped ring at the base of their cock to prevent over-penetration. Maybe that would help you.
She's not being fair about the military career thing.
Your idea of having him move in to cause familiarity to bring contempt seems to have backfired. Healthy 3way living conditions should be to bring more love into the equation, not less. It's almost always a very bad idea to bring a new lover fulltime into your home when you don't know them well. Your wife is just seeing an idealized version of her new crush, and that's very exciting, but not reality.
Love withers under constraint; its very essence is liberty. It is compatible neither with envy, jealousy or fear. It is there most pure, perfect and unlimited when its votaries live in confidence, equality and unreserve. -- Shelley
Mags (poly, F, 61) loving miss pixi (poly, F, 39) since January 2009, living together since 2013
"Master," (mono, 34), miss pixi's Dom for 2 years