Hey Eloise,
Yay for 6 weeks off!
E was vomitting last week and so by the time she was ok she hadn't had dairy for a few days so I said "DH, that's it. While we've already started, we're going to keep going." He wasn't happy, but has agreed. She's still having 15ml lactulose at the moment (I wanted to keep that going for at least a week while dairy free, but DH misunderstood that bit so she's had a couple less doses than she should have. This bug still doesn't seem to be completely gone yet (DH, DS and I have it too

because she had almost diahorrea early this morning (and she DIDN'T have lactulose last night) even though she's been clear of it for a few days. It makes it tricky figuring out what is causing what!
She was prescribed 20ml and to go up to 25ml but we never got that far - her whole insides were coming out and she couldn't control it at all at 20ml so we pulled back to 15ml. 20ml is an adult dose anyway so seems very high for my only-just-14kg-five-year-old. 15ml gives just formed consistenly (I think - trying to remember beyond all the diahorrea of late!). She goes when she wakes up (and we give it as close to bed time as we can otherwise she wakes earlier than she wants to wake needing to go) and probably once more in the day.
At the start she was really excited about being dairy free and having special foods. She's not quite as enthusiastic now that she doesn't like the coconut ice cream (I didn't make it sweet enough though, so will try another batch) and she's not that keen on the oat milk but will eat it. We have rice and almond milk yet to try though and I think almond is sweeter so maybe she'll like that better. She doesn't like coconut cream, so there goes my idea for whipped coconut cream and coconut kefir! :/ She's cried once about not being able to have cream cheese, but really, I'm very proud of her.
In the next week or two they are bringing in a "milk in schools" programme. The first time for a few decades. She's said she will be sad not to be the same as everyone else but understands. Even if we weren't doing dairy free at the moment, I wouldn't want her to have it because of her history.
DH is very skeptical. I've found him a bunch of (medical journal) articles to read (he only trusts professionals) but life has been pretty hectic with all of us sick and him doing most of the looking after us all! He wants to take her to the Dr to get her opinion, which I'm happy for him to do. For a reason I can't really explain, I DON'T want to go with them. I feel like DH is ignorant and arrogant about the whole thing which makes me crazy and I guess I don't want to feel all my anger at him about it in from of the GP? I think she'll be supportive though.
One of DH's main issues is he's embarrassed for her be dairy free. Probably in front of his family mostly (who have zero food issues). I said, "how is it different from any other sickness/condition that you have no control over?" which his head understood, but that's still how he feels. Plus he thinks giving her lactulose for the rest of her life is easier than being dairy free. I agree, it would be but what about the underlying damage it could be doing? Has eating dairy for the past 3 years contributed to her being tiny because it's stopping her absorb nutrients or something?... etc But he says there's no proof of any of those things and it's my fear of those things that has me wanting to do all this.

Sorry this has got long. Ice cream recipe will be great though thanks Eloise!