Ariché

I agree that most of the times just trying to translate sayings literally without explaining the context is not a good idea. The whole point of idioms is that they are often figurative expressions, we might understand the idea behind it but a different language usually means a different culture. There are exceptions, as sometimes those sayings have roots in very old events or common ancestors that makes both languages share some similarities in their idioms. Another reason is also the direct influence of one language over another. At least in mexico, a lot of the dubbing translated expressions into Spanish from cartoons and movies which resonated and ended up being added to our causal vocabulary. In fact I have seen bank adverts in Spanish saying "Moneda ahorrada, moneda ganada", which is pretty much the english expression, except that, since we don't have pennies, they just use the generic 'moneda' term for coin. Anyway, the original point I wanted to make is that, even though an expression might not make sense translated directly, most of the time there will be some sort of saying or idiom equivalent that conveys that same idea. I think finding the equivalent is a better idea, if you don't know it then explaining the saying can be a pretty interesting talk and most likely will wake up in the listeners what they say instead.

Mi alma, mi Reina, angelito, bizcocho, bombón, caramelo, (insert many more sweets here), dulzura, muñeca, Or by her attributes chaparrita, flaquita, morena... I also think from this list cannot be missing "Mi vieja". Although they are usually not as receptive with this one many husbands use this one. Hahah. yeah. Sometimes we think that just by meaning alone we can find the right word but context matters. I've done that, just that insulting friends in English. Just for the record though 'tonto' is more used in the context of like 'dumb' or 'fool and depending the person might be an okay word to use or not. I also think you dodge a bullet, usually "silly" gets translated as 'necio' which we never really use in a endearing way. Necio is more of an accusation about someone being stubbornly saying or doing silly things. Similar to "headstrong". Now for silly you could call him 'bobo' it is another way to say dumb. It works in the similar context you'd use for silly. "Claro que no, bobo" (Of course no, silly). You can call him "bobito" to ensure the endearing context if you're using the word on its own. You can actually use 'tonto' this same way, but while soft, without context people,like I think your boyfriend did, might think it is accusatory.