I am not sure what is OK or not when it comes to suicide, but there may be a difference here. The monk assumidly is not trying to escape suffering arising from unresolved personal karma, while the individual may be. I don't use karma here in the crime and punishment sense, but instead in the sense of unresolved issues or lac of understanding. Commiting suicide to avoid suffering that arises as we try to resolve our karmas is useless. We will only have to recreate the situations that are causing our suffering in another life to work through them.