My "Newer brother" Ginger also has FIV+. AND we have three other kitties who have been with us from 3 years to 13 years. However, when inside we keep Ginger in a separate room, though he does go outside with the others at times. It took us a very long time to accept this all.
But the story in short is that Ginger came to our door about two years ago, with no place to live. He came every single day and actually bonded with one of our older kitties. He was afraid to be touched or pet, just came every day and lay on our steps and we fed him. But he nips at us a lot out of the blue too, even while purring. We finally took him to the vet when he started trusting us more, and he was diagnosed. We did try so hard to try to find another to adopt him or for a shelter to take him in, but we had no luck at all. All shelters said they put to sleep cats with FIV+.
I talked with several vets and cat shelters and caretakers. We finally came up with the most recent news is that FIV+ is not as dangerous as it is considered. It is a very low percentage of a chance for others to catch it. It has to be through a bite, through blood, and if the cat is neutured or spayed, it is much less of a chance he or she will spread it.
The other thing, Ginger (besides being overweight) is completely healthy, and over the last two years he has seemd to be completley healthy all year round. So, we keep an eye on him.
So, at a cat show and adopt show, we had some long talks with those who have dealt with them, and say that they do have a very long, and can live a very long, full life.
Best of Luck. Yes, keep watch and get treatment right away if your kitty gets sick. It is supposed to be easy for them to catch colds easily. Like me; I have a weak immune system.