Dear W.,
As I type I have a really bad cold sore myself. I have tried just about everything there is. I too am not impressed with Abreva. I used to use Valtrex and while that does help it is an expensive medication that is rather strong and I didn't like having to always take it. Plus it has it's own range of side effects which, unfortunately, I am prone to experiencing.
I know of one home remedy that does work but only if you begin doing it immediately with the "tingle sting" of a new sore. Buttermilk.
Personally I dislike buttermilk but in this instance you don't necessarily have to drink it. Do the GOT MILK thing and wear it-thickly only the spot/lip where the tingle is. (I am kicking myself for not having done this day before yesterday as the sore I currently have is a monster..but I'm going out to grab some today.)
I carry around a small cup of buttermilk with me the whole day. I just lift it up like I'm going to drink it and let it get on the spot and I do this every so often to keep the buttermilk wet on my lip. It not only soothes the sting and tingle but if done immediatly the blister will go away before developing. If the blister is already there it will not be as bad. On a full blown monster sore it will soothe it and help it heal faster. I take it a step further and even sleep with it on because I'm paranoid and have been known to just get one in a new place if the first one doesn't come out. Buttermilk has worked EVERY time. Only problem is that I rarely have it on hand. I learned this from my grandfather who is now in his late 70ies. I copy his actions because this is how he does it and strange as it looks and sounds, it does work. I like that it's natural.
The L-lysine thing sounds like it is worth a try too so I may look into that. I'm sure you know that this form of Herpes is triggered by stress, sunlight/burn, and just about any type of illness there is. It is as though the virus gets active when the body is busy fighting something else and can not supress it. Makes sense but how annoying!
Something to consider as well is that it is passed, easily, on to other family members. My husband never got them until a few years into our marriage. He was doomed of course. However, our children do not, yet, get them. I do not allow my children to drink after my husband or I. We do not kiss on the lips with our kiddos (but they've never missed it) and we do not share chapstick, carmex, etc. They have their very own. In tight circumstances I wipe a good layer off of one I use and will then apply it to them with a finger. I probably can't prevent them from getting it one day but I'm trying hard not to be the one that spreads it to them. No one else has mentioned this so I thought I would.
I can't just hide away when one comes up but I would if I could! Mainly, anytime you're sick with anything, or someone in your family is-it pays to grab a small thing of buttermilk to have on hand...
God Bless you and your family and know you are NOT alone! Many of us walk the Earth with an ugly lip from time to time and everyone who sees it doesn't think "Oh gross!" but "Oh gosh that hurts-man am I lucky it's not me right now." :)