It seems to me that we don't give enough help and support to the loved ones of people with mental health problems. If your partner, child, sibling or parent has a mental health problem like an anxiety disorder, depression or an eating disorder, it can place a huge strain on you.

They may be the one who is struggling – and, hopefully, receiving the right help to resolve their problems – but it's easy to overlook the impact that can have on the people around them.

If someone close to you is depressed, you may feel out of your depth as you try to help them. Your normal strategies, like being encouraging or trying to look on the bright side, might not actually be helpful for your depressed loved one – and may even make them feel worse.

Coming up with solutions for the many problems they perceive in their lives might also be unwelcome right now. And we know that depression can be 'contagious', meaning that you might also feel low, or become influenced by their negative and hopeless view of events.

Here are three ways you can help your loved one as they struggle with depression:

1. Understand what they are going through

If you have never experienced depression yourself, it can be bewildering when someone close to you is depressed. But it's incredibly common – one in four people will experience some kind of mental health problem in the course of a year, with the most common form being mixed anxiety and depression. Understanding what depression feels like, what causes it and especially what can help is key.

I strongly recommend Overcoming Depression: A Self-help Guide Using Cognitive Behavioural Techniques, by Paul Gilbert – one of the world's leading experts on depression. You can also find a wealth of information online from charities such as Mind and the Mental Health Foundation.

2. Remember that it's not your job to fix them

When people we love are struggling, it's the most natural thing in the world to try and help them feel better. But when you are depressed it can be incredibly hard to lift your mood, or solve even minor problems that still seem utterly insurmountable because you lack energy, motivation and hope that things will get better.

So rather than trying to fix them or gee them up just listen to them, keep showing them you love and care about them, and encourage them to see a mental-health professional, who does have the knowledge and skills to help them get better.

3. Help them take small steps to becoming more active

When you are depressed, you commonly stop doing the things you used to enjoy – partly because you have no energy, and partly because you don't take much pleasure in them any more. But if you stop doing things you enjoy, or that give you a sense of self-worth, your mood will clearly keep getting lower.

So – gently – encourage them to do small things, such as going for a walk or to the park, doing some gardening, seeing close friends, going to the cinema, or if they feel up to it helping someone else, like an elderly neighbour (we know that this is especially helpful when you feel down).

If they are drinking heavily, encourage them to cut down or even stop for a while, as alcohol is a depressant. If their diet is really poor, try to get them eating more healthily – perhaps cooking healthy meals for their freezer. And if they aren't doing any exercise, see if you can help them start – regular cardiovascular exercise like swimming or brisk walking is as effective as antidepressants for mild to moderate depression.

Finally, if their depression does not lift after a few months, they may need talking therapy such as cognitive behaviour therapy (CBT), or schema therapy if they have had recurrent episodes of depression. You may need to encourage them to see a therapist – this is especially hard for men – but remind them that one in four people experience a mental health problem at some point in their life; and that therapy is now extremely effective, so it's definitely worth seeking help if their life is a real struggle.

I hope you find this helpful – please also remember to take care of yourself, as this will be a tough time for you too.

Warm wishes,

Dan