This starts with a cat

We moved from the city to the country 6 months ago, and now live on nearly 2 acres tucked into the middle of almost-nowhere, surrounded by working farms.
I grew up in a small town in a farming community (in a house with a septic tank and well water) and so have been relearning the tricks of rural living. Max was born and raised in the city but spent years in the bush, living in his hunt camps, hunting and fishing, so it hasn't yet been the culture shock for him that I worried it was going to be. We moved here in part for our business, but also in an effort to leave behind the traffic, noise and human density of city living. We share a dream of living off the grid, growing lots of food, minimizing our impact on the environment around us. We have great plans for blending in to our rural surroundings, but it seems we haven't shaken our urban sensibilities.

I say this because of the cat. The cat, whom we've named Autumn because she is a calico-mix: all oranges and browns and rust, arrived last Sunday. We had guests out for dinner, and were outside chatting when she stumbled up to us, so skinny and decrepit that we all figured she was a very old cat who had wandered away from her home to die. I brought her out some soft catfood (castoffs by our own cat who has finicky and ever-changing tastes) and milk. She ate as if she hadn't eaten in days. Only slightly wary of us (and our eager attempts at comforting her) she gingerly moved into the fading sunshine and tried to sit down - her back haunches stiff and seeminly painful. We let her be, and went in for dinner. After our guests left, I went out and made a bed for her in a box - I couldn't stand the idea of the old girl having nowhere soft for her sore body for the night.
The next morning she was in the box, sleeping. I gave her breakfast and a little pet - I have never seen a cat so skinny and frail. She spent the day in the sun, and was still around at dinner and so I fed her again. This began the pattern of the week - dropping off some food, milk and water, a little petting (and vigourous handwashing after), checking to make sure she was OK. I expanded her sleeping nest into a veritable cat condo - adding boxes and blankets and windbreaks and a roof, all safe in the driveshed.
By Thursday I thought she had put on an ounce or two of weight, and she seemed to be moving a bit better. She started purring this day, and I also saw her try to clean herself for a minute (did I mention that she was disgustingly ratty??). It seems she is a lot younger than we had originally thought, maybe a kitten still. She is very little, but starvation may have stunted her growth, so it's hard to tell. She is missing some teeth, and has clearly been unable (or unlucky?) in feeding herself - it seems that at one point she knew what a home was.
By this point in the week, I was worried about what to do with the poor thing. We already have a cat, who is nervous enough (I hadn't fully realized how hard it would be for a city cat to move to the country) and who doesn't see too well. I didn't know how she would take another cat in the house (and there was no way to let Autumn in the house in the state that she was in - filthy filty filthy and a possible carrier of infection or disease that would sicken our own cat). I asked people at work and thought about family members, but noone seemed to want a stray who was in such poor condition. I went to the SPCA Animal Control to ask about dropping her off (at least she would get medical attention) but they encouraged me strongly to make them a last resort (they are not a no-kill shelter). I started planning a winterized cat condo for the poor thing... something to keep her alive through the oncoming winter.
But over the Thanksgiving weekend, she seemed to improve 100%. She had more energy, her coat looked better, her movement improved. She took to sitting on our porch, or seeking us out for attention. We let her 'meet' our cat (who goes outside also) through the screen door. The meeting went well enough that I started to feel that maybe we could adopt Autumn ourselves. I think she wants a home.
Which leads me back to our 'urban' ways. Out here, people have little regard for strays. Out here, people drop off unwanted animals on the side of the road, left to fend for themselves. Our property is like a highway for strays - we've seen at least half a dozen regularly (and Autumn's food is often completely gone by morning which means she's experienced dinner guests of her own). Out here, it seems that there is a pragmatic approach to animal life - Mother Nature is pretty hard and you can't worry about every creature that wanders about homeless or you'll be overrun by strays. I guess the feeling is that they will either survive on their own, or they won't, and that is the way it goes.
So, here I am with my bleeding heart softness for the hungry, skinny, stiff little cat (kitten?). This morning I am going to call the local vet and see if I can bring her in, to see if she can get shots or pills and a bath to clean her up (inside and out) enough so that I can bring her inside for the winter if she wants. It will probably cost me a king's ransom. The vet might very well think I'm crazy, spending money on a stray (or maybe he won't, he is a vet after all). Then I'm going to have to muster my courage and let the two cats meet (and maybe hiss and scratch a bit?), let the two cats work it out on their own. It will be a learning experience, but I feel compelled to try. It is just not in me to let her "make it or not".
I've got to watch out, though. I need to learn to be more realistic and less emotional, otherwise we'll have a house filled with strays. We've only lived here 6 months and winter isn't even on us, yet.