Help with pronouns

[Mandells]

I am struggling with learning about when and how to use the pronouns, for example, why would you use 'se me ha roto' and not just 'ha roto'?

[Rusty]

You're dealing with different usages here, that's all.

The second phrase, 'ha roto,' means '(it) has broken' - a statement of fact that names no agent (the performer of the action).

If you were handling the thing that broke, and didn't want to take blame for the breakage, you would use the first phrase. The pronoun 'se' is quite versatile in Spanish. One of its several uses is called an "accidental 'se'" construction.
The translation of the first phrase is "I have (accidentally) broken it." The literal translation often given in Spanish-learning circles is "it has broken itself on me" (which doesn't make a whole lot of sense to someone who speaks English).

In the Spanish language, it's very common to NOT take the blame for something you had no control over (even if your handling was careless). Using the accidental, no-blame, no-fault 'se', followed by the pronoun suited to the "perpetrator," takes away all blame.