Firstly I want to say your story could be me! Mine too started in my early twenties and were always triggered by alcohol, I could never understand why my 'hangovers' lasted for 2 days of intense pain and vomiting while all my friends could go shopping the following morning after a night out! I am now completely teetotal, any tiny amount of alcohol triggers me, even chocolate liquors or alcohol used as preservatives in food can do it.
Anyway, about the rebound headaches. In the past year I have had to wean myself off triptans and asparin/caffeine for this very reason. Triptans are a miracle drug for me and like you I can wake up feeling terrible take a Zomig and go back to sleep. I wake up an hour later and feel fine and go on with my day. HOWEVER....over the course of 10 years of this I found I was taking them more and more, to the point that sometimes I would take them for 3 or 4 days in a row....my doctor would only prescribe me 6 at a time and I was forever at the doctors asking for a repeat prescription, I felt like a drug addict but it was the only way I could carry on with my life. I knew that without taking them meant 3 or 4 days in bed probably 3 or 4 times a month.
I was also taking asparin with caffeine almost daily for the inbetween tension headaches.
I read on here and on some other migraine forums about rebound headaches and realised this is more than likely what was happening to me. I am in the fortunate position at the moment of not having to work (am shortly moving back to the UK to am hoping to return to work!) I decided that for a trial period I would only take triptans if it was vital, for example if I had a family event to go to or my partner and I had planned something. For all the other migraines I had I did not treat them with medication I just let them run their natural course. The first two were horrendous I thought they would never end.....over a week for each and pretty much bedridden the whole time BUT I noticed that when they did finally go away I was migraine free for around 2/3 weeks instead of only a few days like before. I still get tension headaches but now I try to ignore them of I take Ibuprofen without any caffeine. I have also cut caffeine out of my diet completely.
I am now down to taking around 4 triptans a month, which is a huge improvement from the 8-12 a month like before. I still get a lot of headaches but they are less severe and often do not need medicating.
I know there is a big debate about whether rebound headaches exist or not, all I can say is that if I can tough it out and let my migraine run its course unmedicated then I do have a longer period of headache free time before the next big one, rather than the daily or alternate day migraines as before.
Hope this helps :)