I had HG with 3 pregnancies (one I m/c at 10 weeks & the sickness stopped that very day)
With the first pregnancy & DD I was constantly vomitting, the worst it got was every 2 minutes, yes we times it... I thought I was going to die & was vomitting blood as there was nothing in my belly left to vomit
The only thing that helps mine is zofran zydis.... it was fantastic! Once it kicked in (within about a day) I could live normally. I did try to come off it throughout each pregnancy but would start vomitting again so straight back onto it. I took it from 6 weeks until the night I gave birth (DD 41+1 weeks, DS 39+2 weeks)
The downside to it is the cost. It costs around $60 for 4 wafers/tablets & you have to take a minimum of one a day (3 a day at the start if its really bad) so it makes for a very expensive pregnancy BUT if you can afford it then its sooooooo worth it, at least it was in my case.
There is no guarantee that you will have it the next pregnancy, fingers crossed that you wont. It's a terrible condition that I wouldn't wish on my worst enemy.

I hope I've helped