Not if she has AIDS. She's going to probably die soon. I wouldn't want to be emotionally invested in someone who's on death's doorstep.
Now, if she's just HIV positive (and not afflicted with AIDS), the answer is still "no". I don't want to die, ever. I know it's coming though. I don't plan on doing things to speed that up, at least not knowingly. Sorry -- too risky. It'll feel like I'm always looking over my back, wondering if the next test will be positive. And then stressing about the thought of going HIV to full blown AIDS.
Each time you have sex, you've got to wait 12 weeks for your body to sero-convert. That's a long 12 weeks. 3 months. An entire season. Wondering if you've caught something that could kill you. No thanks. I will never love any woman enough to do that to myself. I have too many people counting on me to live and be healthy into my old age...I can't be flippant with my life.
I know researchers believe the prognosis for life is better for someone with HIV versus someone with type II diabetes now, with all the drugs they have. I still don't care. I don't want HIV. I won't do anything to put myself in a position where I could get it.
If my wife cheated on me and caught it, we'd be done. Instantly. I would expect her to do the same to me. One of us has to live long enough to take care of the kids and see them grow up.
Sound heartless. But this is one of those very few clear-cut decisions for me.