Training a cat to use a catflap - help please!
First time posting on here but you all seem like a friendly knowledgeable bunch so thought I'd ask your advice.
We have two cats, Merlyn is a 10 year old girl and Zebedee a 9 yr old boy. We've lived in our house for 7 years now and have always had a 'cat-hole' in the back door, basically a catflap with no door! When it was first installed Merlyn refused to use it, growling and hissing and getting stressed, so we removed the door to make it easier for her.
Over the last few months we've had an increasing number of other cats coming in the house eating our cats food, fighting with them and spraying. Zebedee started jumping at every little noise and Merlyn wasn't happy at all, so we installed a magnetic catflap to keep the intruders out. Zebedee figured out how to use the door and has no problems but Merlyn refuses.
I've tried tempting her out with milk and treats, talking to her, stroking and reassuring her but she just sits there and growls at it. I've resorted to blocking the way back into the kitchen and gently nudging her bum so the only way she can go is out the catflap. Her growls just get louder then she eventually noses her way out, she has no problems coming back in after she's had a wander and play in the garden and done her business and I usually reward her with a treat on her return.
So do you think she's scared or just being stubborn. Am I going about it in the right way or should I be doing something else?
Any advice would be much appreciated!