Good questions!
Re hair, I was on A/C first and was told two weeks. It started dropping after 2 weeks and one day. After that, it was all pretty rapid. You may be advised that you will get some "tingling" - after the first 3/4 days my scalp felt like it had a bad case of sunburn, quite uncomfortable. After about 5 days, my hair simply didn't feel like it belonged to me at all. It looked OK but felt really odd. The good thing about that (you'll get used to finding good things when you can!) is that it made it much easier to go and get it cut off!
No, you won't kill your husband but it does depend a bit on what chemo you are being treated with. My oncologist gave me written information(and verbal) on all of this before I started, which was really helpful. A/C is pretty full on, so the advice was no sex in the first week after every treatment. Which is also when you need to flush twice, and be careful if you are sick - cleaners uppers need to wear gloves and use bleach - not pleasant, but on the positive side (there I go again) I was never sick! Bottom line, you really don't want to share any of your bodily fluids with anyone while the chemo is going through your system. A 3 weekly treatment will take about one week to get through your system, as long as you are not constipated or anything else fouls up. A weekly treatment, such as Taxol, about 3 days.
We didn't use condoms, but that's an added protection.
Good luck! This too will pass.