'Instead of just sitting by my side, she knew she had to get help'

When I first got my cat Charley, she was a tiny kitten, no more than five weeks old, and she wasn't eating. Her owner was at her wits' end and turned to me for help.

I took in this tiny scrap of black and white fur, and began to coax her to eat. I posted morsels of kitten food into her mouth every four hours and kept her basket by my bed so I could monitor her day and night. Charley began to rally and, as she grew, so did her attachment to me. She would never leave my side.

At times it became annoying, especially when she kept getting under my feet. She was so attached to me that she resented anyone else coming near. If my husband, Kevin, showed me any affection, Charley would wedge herself in between us. I had two other cats, but they were closer to Kevin and my daughter, so Charley became "mine". It was on her terms, though – as they say, a dog has a master, a cat has a slave. I was under no illusions that cats are anything but selfish.

I have been diabetic since I was 12 and need two injections of insulin a day. I can usually control my diabetes well, but once or twice, usually due to illness or exhaustion, I have ended up having a bad hypo, or hypoglycaemia, when your blood sugar drops to dangerously low levels, causing dizziness, palpitations and even loss of consciousness. Normally during a hypo, you can recover by eating something sweet, but sometimes the attack is so sudden, you don't get the chance.

I had been Christmas shopping all day and came home exhausted. I had some food and went to bed, but I obviously didn't eat enough, because that night I can remember getting up to go to the loo… and then nothing. My blood sugar must have dropped during my sleep and I collapsed in the bathroom.

Within minutes, the cat realised something was wrong. Instead of just sitting by my side, she went to our bedroom and jumped on the bed where Kevin, always a heavy sleeper, lay undisturbed. Then she began to pat his hand with her paw and lick his face, something she'd never done before.

We've no idea how long she continued this, but it must have taken a while for her to rouse him. He woke up because she was licking him, but he shooed her off the bed and fell back to sleep. Charley didn't give up, though, and kept on patting and licking, all the while making a strange squeaking noise that my husband had never heard her make before.

After batting her away another couple of times, he finally sat up. Charley instantly shot off the bed and out of the door. Kevin noticed that my side of the bed was empty, and followed the cat to the bathroom, where he found me unconscious on the floor. Thankfully, he had been trained in how to give me an injection of glucagon, which makes the body release glucose, and within minutes I came round. "What am I doing here?" I asked groggily.

Kevin told me what had happened and I couldn't believe it. Charley had actually made that logical jump – if she couldn't help me, she'd get someone who could. It still astounds me. You hear about dogs coming to the rescue of their owners, but cats are known for their independent spirit. It seemed so odd.

As I recovered with a drink and some toast, Charley sat on my lap, purring. She slept by my side that night, and the next day hovered around me. My other two cats slept through the whole thing – much more typical cat behaviour.

If Charley hadn't raised the alarm, who knows what would have happened? Would Kevin have woken up in time? I doubt it. Most probably I would have fallen into a diabetic coma, suffered brain damage, maybe died. Instead, thanks to Charley, I didn't even have to goto hospital. Soon after the incident, Charley got very ill with cat flu. It was my turn to look after her – the relationship is reciprocal.

Now I am more careful with my blood sugar levels – it has taught me an important lesson. It shook Kevin that I could become so ill so quickly – he hadn't had to inject me before. We were both so grateful to the cat.

• As told to Emily Cunningham

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