"If you looked through the window you’d think we were the perfect family but it’s tearing me apart. My friends say I should kick him out and only then will he realise what splitting up really means, because at the moment he’s having his cake and eating it."
More: I can't keep living a lie with my husband - Coleen Nolan problem page - Mirror Online
1- "Have your cake and eat it"
2- "Have cake and eat it too"
Does dropping the adverb too right here as Rover said "expecting listeners to finish them for themselves" or it is an optional?
You could drop more than that and expect people to understand. It's such a well-known saying, you could probably get away with "He's having his cake ..."
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.