Mine started at 4 weeks, was horrific between 6-8 weeks where I was pretty much bedridden with it, and it tailed off at about 9/10 weeks....I've been sick once since then and it was a real sprint-to-the-loo job, came from nowhere. I found it was worse when my sense of smell was most heightened, as soon as things started to smell normal again the sickness waned. I still have the odd moment, though.
And of course we can't win, because instead of feeling happy and relieved that my sickness was abating, I worried that it meant something was wrong with the baby!! Only after having my 12 week scan today do I feel a bit better about it all.
So don't worry, the sickness will pass for you, just got to ride it out. I felt like mine would never end but it did, and pretty abruptly too. Take care.xxx