Hello Sky,
Sorry to hear you two are going through this, regardless of what it turns out to be.

Yes, it is possible for someone to carry herpes in their system for years without getting symptoms...or without getting symptoms that you connect with herpes. Other symptoms include flu-like symptoms that don't develop into a flu, itching and/or tingling at a particular place in the genital/pelvic area, etc.
The top of the buttocks is a somewhat common place for outbreaks. I've had them there for years. It's not necessarily the place you got it initially, but it can spread to that area through the nervous system. I find the sores will ooze onto/through my clothes, so I usually put a sanitary pad or pantyliner there, attached to my panties. This helps keep the sore dry too. Your husband might not be very comfortable with using a feminine product though, so a bandage taped to his underwear might be helpful. Tylenol and/or applied heat or ice to the area might help the pain.
Your title says "suspect husband," which sounds like you're questioning if he might have picked up herpes in an extramarital affair. It's an understandable concern and might be the case, but not necessarily. For that matter, it's about as likely for you to have carried herpes for years without symptoms and for him to have caught it from you. About one in four people has genital herpes and most of them don't know it, but they can still pass it on.
I'm not a health professional, but I'd strongly recommend that you both get blood tests now. Be sure your doc uses a test that distinguishes between types 1 and 2. If you both come back negative for HSV-2 (the usual cause of genital herpes), get tested again in about 4 months. If one of you tests negative now but positive after 4 months, then you know that they contracted it very recently. If one of you tests positive for HSV-2 now, then it's probably been in their system for at least 4 months.
Don't be surprised if either you tests positive for HSV-1, since this is the usual cause of cold sores. Up to 80% of the population has HSV-1, caught during childhood from contact with relatives and friends. It's possible that your husband's sores are caused by HSV-1, typically transmitted to the genital area through oral sex around the time when the giver has an active cold sore.
You're also wondering if your anal itching could be the same thing. Yes, it's possible, even without anal sex. I'd strongly suggest you get yourself checked out ASAP too. Get the doc to look at it and take a swab culture. Just be aware that culture tests often return false negative results. If the symtpoms come up again (for either of you), get a swab test immediately (within first 24 hours) for best chances for accurate results.
Good luck! Sorry this is so long but I hope it helps. Let us know how you make out.
TheOneInFour