I am afraid a lot of these tragic events are down to the Welsh mentality and backward way of life. Also their high incidence of ritual child abuse, animal torture and lack of moral education adds to the gruesome statistic.
They may have free prescriptions and relatively nice scenery, but human beings have to have a sense of belonging. Whilst Welsh national identity and pride are very high, maybe even more so than the English, when they become aware of what they are basing this pride on, I am afraid the illusion is shattered. This realisation they they are living in a British Beirut occurs around the teenage years, hence the high suicide rate.
They see their parents and many do not realise nor accept there is life beyond the Severn bridges. Likened to Hobbits, I am sad to say the Welsh are a very insular people.
That's what I think is going on anyway, as you asked.