I'm a married man so it is no longer applicable to me, but in the past I dated girls from other countries and through those relationships I became a much better speaker of their languages. People on italki seem to be dismissive or judge with suspicion those who seek romance on this website, and perhaps rightly so, but is romance not a legitimate means of improving language competency? 

When I lived in Japan I came across plenty of girls who wanted to date Westerners primarily to improve their English level (yes there were many girls who had other motives too*). Is this a legitimate route to higher language competency?

I'm interested in hearing all points of view:

Have you ever benefitted from improving your linguistic level through dating?

Are you a linguistic assassin who always trains their cupid's arrow on those who speak your target language?

Have you ever been the "victim" of a linguistic assassin who was dating you only for your language and then who left you once you had ceased to be useful for them?

Or are you or have you been in a simbiotic relationship where both of you linguistically feed off each other?

Let's hear thoughts from all sides.

*Best discussed elsewhere