Looking for help and advice please.
Dcat is around 13 years old and was feral when we got her, she had been one of a litter born on a nearby farm and the farmer asked us if we would take her while he had the mum neutered. She wasn't a tiny kitten when we had her but only a few months old we think. We expected she may remain semi-feral and might mostly live outside but in actual fact she domesticated really well, bonded with our older cat and although she's not a lap cat she does now enjoy and actively seek out human company and fuss and attention.
She has always been a nocturnal cat and a big hunter. She sleeps all day, usually in the same room as whoever is at home that day, and then goes out pretty much all night hunting. She has a flap so comes and goes as she pleases.
Around 3 or 4 months ago I was woken up in the night by a lot of caterwauling and went down to find her squaring up to another cat I didn't recognise. I brought her in and didn't think much more of it. This happened again several more times although on these occasions when I went down she was hiding under one of our cars rather than squaring up. Last month she had a nasty bite wound that needed vet attention to heal. We had the same last week and again last night. It's always the same cat and it doesn't belong to any of our nearby neighbours - we're in a small village so know most people locally.
I am wondering if I should start keeping her in at night but I really feel this would make her miserable. I'm also worried this might give the 'new' cat opportunity to take over her territory and actually make things worse. Equally however I don't want her to be hurt and having to fight constantly to maintain her territory - not to mention the expensive vet bills.
Any advice gladly received as I'm really not sure what to do at this point.