They were uneducated comments from a child with very little experience of the world. It really is as simple as that. A lot of people think suicide is selfish as they don't understand. There is no punishment, just being ill. Depression can be caused by trauma, bereavement, illness, hormones, chemical imbalances... so many reasons but not punishment. You are ill and you will not get better unless you allow yourself to get treatment. You just need to decide what treatment you want. Some people just go for counselling, some just for medication, some for a combination of both. Moderate to severe depression, the recommended treatment is therapy and meds.

If you try the medication route, it's important to remember that they take 4-6 weeks to start working and the same with each dosage change, side effects can last up to 2 weeks, sometimes it takes trying a few different ones to find one that works, and there are around 21 different licensed ADs and other psychiatric drugs they can try. Above all, your GP legally cannot discuss your medication with your family as they would be breaking patient confidentiality.

If you try the therapy route, the main types used are counselling (talking therapy) and CBT. Counselling helps you work through things, the counsellor shouldn't give advice, but instead guide you as you work through things. CBT works on changing behaviours. You may be offered one or the other, or even integrated therapy, which is both. Again, therapists are bound by client confidentiality and can only contact others, and then I think it's only the police or your GP, if they think you're a danger to yourself or others. If they did otherwise they would be struck off.

Mind sometimes run groups. You could contact them and see what help they offer, it would also get you out of the house and maybe start breaking the cycle you're stuck in. Look at meditation too.