Believing in a higher power, or more appropriately, having a relationship with the divine, gives your life meaning.

A meaning that is completely lacking in an atheist. Unless they aren't really an atheist, and sneak behind everyone's back, and has a relationship with the divine, but they call it nature, or the universe (or some other aspect, that are all reflections/parts of the divine)

You commit suicide when your life has no meaning, no purpose, no future.

One of the biggest areas of suicide, (that no one talks about, it is actually an epidemic), is father's who have been summarily separated from their families by the evil of divorce court.

These men used to a have a life of meaning. That meaning was their family. They worked hard to support their family. And then a judge tells them, you have no family, but, you will work hard and send all you money to a never ending sinkpit . To these men, there is no future. Their life is now meaningless.

The only way out is to set yourself on a higher meaning.
And yes, getting angry at your ex will keep you alive.
Because apathy, the lowest emotion, is where you commit suicide.
Although not a positive emotion, anger is higher.