Never really had the problem of unwanted attention from family, friends, partner. I just say "I need to sort myself out" and they ignore me, unless followed by "I need to eat now" or "I'll need to eat soon". If you don't want them to ask, don't let them know you're testing / injecting. Also, having testing kit and insulin each in 2 places in my own home (kitchen / bedroom / bag that I take out & about) helps to be able to go somewhere private.
My lack of problems is because I was diagnosed aged 30 years, when unfortunately living with parents and semi-house-trained 19 year old cousin, having just returned from overseas, nearest friends 100 miles away, and as this was 1996, no internet nor mobile phone. So, I made it clear to my Mum that I would sort things myself and eat whatever I was provided with (fussy Dad and cousin made this very frustrating, although once an Indian doctor friend brought me home cooked curry). This became much easier when, after a few months of bimodal insulin, I changed to MDI, because the pharmacist mother of a friend of mine (we'd gone on holiday to Belgium and she'd seen that injecting 30 mins before breakfast & evening meal was somewhat inconvenient) sent me a photocopied article about MDI / basal bolus regime, and I asked clinic to change.
My partner (met in 1999, some 3 years after diagnosis) knows that I adjust my basal insulin dose according to general activity / weather, and bolus insulin dose according to meal contents. But he has no idea of my typical doses - why the heck does he need to know, if I always do my own injections? He is good at causing a diversion if appropriate. If he cooks, he usually tells me / shows me plate before I inject. However, had a bit of a hiccup last night when he cooked roast duck, showed me pototos, but forgot to mention there was blackberry crumble in oven, so I decided not to have another injection for pudding, but to eat some tonight.
Most friend and colleagues don't know about my diagnosis, although I don't mind them knowing once they've known me for several months. It's particularly fun to surprise medical / nursing colleagues and friends, as most have noticed my adventure racing / navigation skills or nordic skiing to work, rather than having any inkling about type 1 diabetes.