Chemo - what's it actually like?

[babysaurus]

A good friend is having a second bout at chemo as, despite hammering it with the sessions she had at the end of last year, it's now in her liver and brain. It's terminal but she wants to, obviously, last as long as she can.
She tells me bits (I don't ask, but listen if she brings it up) but mainly says its just horrendous and the nights are the worst. I imagine its like the worst kind if stomach bug and then some, but don't really know.
Can anyone who has been through it, tell me please? Also, are some forms far more hArd hitting than others? Am guessing so due to her situation.
Thanks