Many crew get live-out allowance, which is pretty easy right now. When I joined they only gave it to married crew, but now there's a shortage of crew accommodation, so they will easily give it to anyone. Yes, it's against the law to live with your boyfriend/girlfriend, but many people do it and Dubai is not the hell some people paint. It's very unlikely you'll get reported, unless you shout it out loud.
Bear in mind cabin crew live-out allowance is not that amazing, but if you both get it you can rent a decent place in Dubai. Many live in the neighbor emirate Sharjah, where rents are cheaper.
It's impossible to live in EK accommodation with non-EK cabin crew/different sex crew. If you are same sex and both cabin crew, you can apply for a 2-bedroom crew accom.
If you wanna do long-distance, your significant other can visit for up to 60 days per year (not over 30 days per visit, as I remember) and whoever it is you can just put them as cousin on the visitor form. EK is not stupid and they know what it means. We've all done that.