We don't have the USA Patriot Act in the UK.   There are laws that would criminalise those kinds of activities, though I suspect a bit more carefully drafted.

But I'm not sure how the kind of things Shamina has been involved in would fit into any of those headings. Could just being married to an Isis fighter be counted as "service" or ""providing material support for terrorism"?

The thing is, having nasty beliefs in itself doesn’t count as criminal. There has to be some kind of action involved, outside places like the Isis Caliphate. (Of course a way for a government to crim8nalise beliefs is to require some kind of loyalty oath or its equivalent. But we don't have that for civilians.)