I'm the same as Judge, I've suffered with depression my whole life (now on Prozac for several years, on and off). Several years ago I twice tried to commit suicide due to the depression and also being in a very abusive and violent relationship. Both times I was lucky, and my mother - who I have never ever got on with - was the most supportive person in the world to me, and still is. My sister however, told me I was very selfish and I didn't care about anyone but myself, and if I ever did it again she would never talk to me again. That was NOT the input I needed, and there is now quite an emotional distance between us, as what she said really, really hurt me.
You really need to get your relative to the G.P, and perhaps get them some counselling, I hear CBT is amazing for most people, I had traditional counselling for 2 years and it really helped having someone reaffirm what I already thought and also support me without judging me. If not, as Bibblebub mentioned, the Samaritans are amazing and may be able to convince your relative to seek other help.
I really, really feel for you, and I hope things get better soon.
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