I forgot to talk about BG testing from finger pricks. Clearly it is your choice whether to do this. My (non-medical) opinion is if someone doesn't test then it's akin to driving a long distance without ever checking one's speedometer (or worse with a filthy windscreen!). It's in my DNA somewhere to know what is going on and check that is happening whenever possible.
If you decide to test, the Nurse's advice is total nonsense. Once a month unspecified make less than zero sense. Every morning, immediately after starting to get up, would provide a series of reference results about your BG at the end of one's natural fasting period; or once every week; even only once a month for 12 months - BUT always 1st THING. However an even better use of finger prick tests is immediately before a meal and then exactly 2 hrs after the 1st mouthful would provide facts about how well (or badly) your body is managing that particular meal. Structured meal checks, done systematically, would allow you to find your optimum breakfast, then lunch choices that are fine for you both weekdays and weekends; then narrow down evening meals, including from social outings as well as when home.
@Leadinglights has spelt out suitable target numbers. Don't get dispirited if it takes a while to find YOUR great meals; it's a complex business in practice finding what food item works well enough for you when in combination with any other food item. We are all different so what works for one person, may not work for you. Porridge is an excellent example of that: for some it provides the lasting nourishment without spiking your BG; for others it's plain rocket fuel!
Structured testing is essential, otherwise you have random numbers that tell you nothing. Being systematic makes it easier: work out one meal type at a time, then move onto the next meal type. A single result is an indicator; 2, better 3, fp tests for each meal that seems great for you gives you some reassurance that you don't need to check that particular permutation in the short or medium term.