OK after reading LOADS on the subject, I still can't find a direct answer to my question!
If Herpes is a disease, how does it affect my life?
You have a lot of great questions and I'll try to address each one.
Your first question is an easy one. Herpes is not a disease, it's a virus. There are two kinds of herpes that are related and they are Herpes Simplex Virus 1 (HSV-1) and Herpes Simplex Virus-2 (HSV-2). The main difference between HSV-1 and HSV-2 is their site of preference. HSV-1 prefers the oral region while HSV-2 prefers the genital area.
The majority of oral herpes cases (often referred to as cold sores or fever blisters) are caused by HSV-1 and the majority of genital herpes cases are caused by HSV-2, but both type-1 and type-2 can be contracted in the genitals, oral area, or both.
And if it's just a skin infection, how long does it usually last before it goes away? DOES it go away? Or is it something I live with for the rest of my life, simply learning to manage the outbreaks?
There is no known cure for herpes so, as of now, the virus itself will not go away. However, the outbreaks do go away. Recurrent outbreaks can last anywhere from 2 to 12 days.
But I have been getting the same cold sore on my lower lip for over a year now. I have a bad habit of picking at anything that appears on my skin, so I do that to the sore every time it comes back and I let it grow into something of a bruise. Then it heals, but it usually comes back later as a sore bump and so on and so forth.
But it's just the one! I haven't gotten any other cold sores *anywhere*. Not on my genitals and not on my mouth or inside it or anywhere. So I suppose it is possible that it's not a Herpes symptom so much as a bruise/scar that I haven't let heal!
I cannot diagnose over the Internet but what you are describing is consistent with oral herpes. If it is, you may be surprised to know that the majority of the population has oral herpes. Many people have it and don't even know it because they never had a sore. There are others who get a cold sore on a regular basis and don't know it's HSV-1.
Is it possible I contracted Herpes from someone else before him (though that would have been... three years ago) and have been getting the one cold sore since - even though I clearly havent passed anything onto him, orally or otherwise.
Yes, it's very possible to contract HSV-1 at almost any time in one's life from being kissed on the mouth area. A lot of people actually contracted HSV-1 when they were children. Some adult (who had cold sores)probably kissed them on the lips and they became infected.
This brings up a sidebar. Back in the "olden" days (as my kids would say) people did not understand that cold sores and HSV-1 were one and the same. I had a slight argument with my Mother-in-law a few years ago because I told her that her cold sore was herpes and asked her not to kiss my kids until it healed. She was not amused and genuinely thought I was trying to be hurtful. Many people in the older generation (and some in this one) refuse to make the connection simply because of the stigma attached to the word "herpes".
So confused. But mainly I want to know - does Herpes stay with you for the rest of your life? Or is it like, well, a yeast infection or the flu?
HSV-1 is in a different catagory all together than a yeast infection or the flu. Yeast infections can be cured with medications and once th flu runs it's course (there is also no cure) in the body, it's gone. HSV-1 is not curable but the outbreaks are treatable.
I hope I was able to answer your questions!