A good Samaritan is empathetic and listens to people's darkest thoughts in an open-minded and non-judgemental manner. As I've not really seen you respond on others threads that often on here, I couldn't really comment on if you'd be good or not. Having depression does not automatically make someone a good Samaritan, it just means that they understand. Those other qualities are more important. I do agree with the others though that you may find it difficult if you're often feeling suicidal yourself. Maybe walk before you can run?
If you're serious about training to be a counsellor, I'd advise doing a lot of research. You need a level 4 diploma in counselling skills as a minimum. Level 1 and 2 are around 7 weeks each, level 3 is roughly 25 weeks and level 4 is around 2 years part time. Level 4 includes client work. You need to have student membership of BACP, have around 100 hours of client work, pay for around 20 hours personal counselling and pay for supervision too. You're only qualified after completion of level 4 and then need full membership of BACP. The costs I' looking at are £125, £220, £660 and almost £3,000 a year respectively, though level 4 is eligible for a tuition loan.
