Don’t worry about all the questions, that’s what some of us live for - ways to make our hard earned experience pay off for other people.
Have you looked at https://www.mstrust.org.uk/about-ms/ms-treatments/ms-decisions-aid There are details on the decision aid about the different drugs.
It’s a difficult decision, choosing a first DMD. And the ones you’ve been offered vary significantly.
I always thought I’d been cheated out of Lemtrada as it wasn’t in use when I was first diagnosed. I actually went to a lecture by Dr Coles about what was then called Campath in about 2002. It sounded amazing, but it took many years to become licensed for RRMS and actually offered to people. So there’s a bit of me that wishes I’d been a suitable candidate for it however, it’s a heavy duty drug (big gun) and has the potential for significant side effects. So think carefully and do plenty of research. You’ll find a lot of people on the https://shift.ms/ forum have taken it, so look on there. (There should be some posts on there about Ocrevus too - it’s quite new so there’s less anecdotal information about.) You could also look on here for posts by Katy79. She’s written plenty about her experience with Lemtrada.
Tecfidera is a different kettle of fish, being an oral therapy which is also lower down the flow chart of both effectiveness and side effects to both Lemtrada and Ocrevus. There was some evidence that Tecfidera works best when it’s the first DMD a person has taken. I’d point you to the right place for that evidence, but it seems to have vanished. It is a good drug and is possibly a reasonable first DMD to take, if you’re not having relapse after relapse. It still has side effects, some people have quite a bit of nausea. Quite a lot of people (me included) have to stop taking it due to depleted Lymphocytes. Lymphocytes are the white blood cells responsible for fighting off viruses. So if they are too low, you have to stop the drug and it can take a while to recover the lymphocytes. But that actually isn’t so bad I don’t think. Two different neurologists have now told me that the time it takes your lymphocytes to recover, you are still fairly safe from assaults on your myelin by the immune cells. Certainly if you take Tecfidera and decide it’s not for you, you can scale up to one of the other drugs. The problem might come if you did have lymphocyte depletion, you could find you’re then not a suitable candidate for Ocrevus as that has the potential to lower your neutrophils (the kind of white blood cells that fight infection).
I suggest you get family/friends to look at the drugs if you can and talk it over with them. Whatever drug you take will affect your nearest and dearest too, so it’s no bad thing to get them invested in the decision.
And it goes without saying that you can keep debating pros and cons on here.
Re your life insurance, I’m not sure. It sounds like you’ve started the ball rolling with DVLA. Not certain whether there’s anyone else who needs to know. It’s always worth seeing your GP to talk about the diagnosis. Make sure they are aware of your diagnosis and what future needs you might have. See how much they actually know about MS!
I’m glad you have now been given the definitive answer by the neurologist, that it is MS. Hopefully, you feel ok, maybe a bit less uncertain.