Listen, Amy has to talk.

The first sentence is misspelled, Demeese Libra.

The third sentence is wrong. If you write to him, it should be Escríbele una carta. You can't use se at this time. Pay attention to your accent.

Everything else is right!

Se(nos, os) is used for mutual tense.

Like Luis y yo nos ayudamos.

What is necessary is communication.

Mutuamente or recíprocament are sometimes added to reflect the ambiguity between them.

For example: ellados sevisten (mutuamente). There are two interpretations of the sentence without mutuamente, that is, both wear clothes or wear clothes for each other, and mutuamente eliminates the ambiguity.