...is Aldara really so horrible and does it have to be used over a whole 5 months?
Aldara is typically used for up to 16 weeks, although warts often respond sooner. Even when Aldara doesn't remove all the warts, it can reduce them in size so that removal by another method is easier.
The skin irritation caused by Aldara is typically described as mild, but some report that it was very uncomfortable and they stopped treatment for awhile. There's a whole range of responses here, as you might imagine, usually not too bad but the irritation is more pronounced for some. I've never heard of anyone using the cream regularly for five months, and expect that doing so would greatly increase the odds of severe skin reactions.
It's true that experts don't know if HPV is totally cleared or if small, undetectable amounts remain hidden in the skin cells. Some people do have warts come back years later, but I think this is most often observed in someone with a very badly compromised immune system (chemo, organ transplant, major illness). Long-term recurrences are not a normal pattern, but there are exceptions.
I hope this helps!