NMO for my controlling ex? *MNHQ ALTERED TITLE*

If you get an NMO, then yes it could involve no direct contact (i.e. correspondence only by, for example, solicitors). It'll work both ways though, you would also have to communicate everything through a solicitor which will not be free.

There's also the question of the merits of your application for an NMO, which will depend on what you actually mean by "intimidation and down right nastiness." It's important to stress that NMOs are not easy to get without evidence and the courts take a much more stringent view on what merits an NMO than many support groups such as Women's Aid (support groups tend to view domestic abuse as a gendered problem, whereas the Family Court are much less inclined to do so). So for example, your evidence would be the text messages although the court would look at them in context (i.e. they would want to look at the whole conversation, not just the messages he has sent). A solicitor will be able to help you determine whether an application for an NMO has merit.

That said, it would seem to be common sense for both of you to stop corresponding directly with each other, on the assumption that you are already not living together. The threat of an NMO might be enough for him to not want to communicate with you any further. This seems to be a divorce with high conflict and there seems little point in trying to resolve matters directly with one another.

You can also (and much more quickly and cheaply) get a new number for yourself while putting the old SIM in a cheap handset and giving it to a trusted friend who can pass on the relevant factual content of any messages to you while filtering out the rest of it.

Possibly. Although if there is abuse going on then if at all possible - and if the OP feels up to it - it would be worth being aware of it, collecting the evidence and if appropriate getting an NMO.