The new term is well under way and already I feel like I've been struggling to catch up. I had the most wonderful Christmas, but since then both my husband and I have been dogged with illness. New Year came and went with no let up, then the kids went back to school and life continued to seem like a blur.

Friends asked if I'd made new year's resolutions, but I replied that I was frustrated that I hadn't had any time or space to reflect on the previous year and pray through my goals and vision for this year (something I like to do every January). I hadn't even got my office in order or put up a new calendar.

A few days after the kids went back to school it suddenly dawned on me how down I felt. It wasn't that anything awful had happened – and, as I've said, we had a lovely Christmas. But the constant pain and problems in my body, combined with a lack of sleep, were taking their toll on my emotions.

I knew I was responding negatively to people – my husband, kids, others around me – and was desperate to do something about it. But I also knew that I needed time with those who would do me good rather than just pressing through and trying in my own strength. And that meant spending time with God – and booking a lunch date with a friend who both encourages and challenges me.

Over lunch we talked and cried, and I left feeling lighter. The following morning I couldn't get the phrase 'For yet I will praise Him' out of my mind as I drove back from dropping the kids off at school. I had been saying to God that I was frustrated with myself; there was so much I wanted to get done, but I still felt like I just wanted a date with my duvet.

I came home and looked up the phrase, finding it in three psalms. Here's one from Psalm 42:5:

"Why, my soul, are you downcast? Why so disturbed within me? Put your hope in God, for I will yet praise him, my Saviour and my God."

Something inside me leapt. I realised that, like the psalmist, I needed to speak to my soul and remind myself to put my hope and trust in God.

I find that I have to do things actively that focus me on the positive when I am in a low mood, as otherwise my mind quickly spirals downwards and I can wallow in what feels like a pit of despair. I was reminded of something I encouraged us all to do last January in a column for Christian Today – be thankful.

I looked back over the Christmas period and came up with five things that I felt I could be thankful for over that time and then posted them to Facebook before I started work. Here they are:

• A lovely time with our parents, especially poignant as we didn't think mum would be well enough to travel 

• Our wonderful new log burner – it's been so lovely and cosy

• Thoughtful friends who show they care deeply

• Kids that were simply delighted by everything to do with Christmas

• A 'handy' husband who built a fab new window seat even though he was feeling rubbish

As you can see they're all quite simple things. Being thankful isn't rocket science – it's just about stepping back and noticing the little details of your life that bless you.

I am still having to choose to be thankful and positive, as I'm still feeling under the weather – and especially in the moments when the waves of low mood catch me unaware. But I know that God calls me to be thankful so it is worth the effort: "Give thanks in all circumstances; for this is the will of God in Christ Jesus for you" (1 Thessalonians 5:18).

Even when I am good at being thankful it doesn't mean I am ecstatically happy all the time. But I have to say I am very, very thankful for a God who meets me where I am at – and this unexpectedly difficult start to to the year has been a timely reminder of that for me.