break down/up

[The Dude]

LONGMAN:

break down:
2 to fail or stop working in a successful way:
I left London when my marriage broke down.

break up:
5 if a marriage, group of people, or relationship breaks up, the people in it separate and do not live or work together any more: He lost his job and his marriage broke up.

Can we say that 'my marriage broke down' roughly equals 'my marriage broke up' in the above contexts? Or is the 'up' closest to 'completely' in meaning?
Thank you again.

As fivejedjon says, yes - roughly. But I think the Longman definitions are clear and correct here (better than your earlier one). Whilst 'break up' in this context indicates the finality of the separation (divorce), 'break down' emphasizes the process of gradual deterioration in the marriage. A marginal difference, but worth noting.

[henz988]

Whilst 'break up' in this context indicates the finality of the separation (divorce), 'break down' emphasizes the process of gradual deterioration in the marriage.

That's what an ESL wants, at least it makes me comfortable. I don't know why.

Thanks.

[5jj]

That's what an ESL wants, at least it makes me comfortable.

If by that you mean that you want a clear answer, remember that a clear answer may not be the only answer - it may not even be the right answer! My own opinion is very similar to Dude's, but I think we would have to analyse a lot of authentic examples before we could state categorically that this was the correct and only interpretation of these two expressions in the context of the ending of a marriage.

Note that I began my previous answer with "For me, and I stress that this is a personal view....".

[henz988]

Yes, I totally agree with you.
That said, I feel it dreadful for an ESL. It seems that an ESL could never learn to be an idiomatic speaker without immersing in the target language for quite a long while. We always need some “simplified rules” to guide us on a commoner ground, and that, on the other hand, will always single us out as a nonnative speaker.

[The Dude]

Don't worry about being easily identified as a non-native English speaker. Whilst you naturally want to be as fluent as possible, you are right to realise that perfect fluency would only come after a long stay in an English-speaking country.

Personally, I am always delighted to meet a non-native speaker - I see someone who's making the effort to learn my language and I feel this is an honour. My French is not good, but whenever I'm in France, speaking poor French without embarrassment, I find that people are especially attentive and helpful. They don't see it as a problem, so neither do I.