I've been on the jabs since March and down to goal last week!
I don't like lying about them, because that feels to me like something a person would do if they're ashamed of something (which of course I'm not). I also think lying creates a stressful situation, where once you start, you have to keep it up, otherwise people will know you were initially being dishonest. I'd hate to be forever stressing about getting "caught" in the lie, too.
I didn't bring the jabs up in conversation either, mainly because I didn't want to bore people with details of my health / diet. But anytime anyone asked about my losses, I was matter-of-fact and honest. Or if people started talking about the jabs in the general sense, I'd get in quick and say I was on them, because I didn't want an awkward situation where they said something negative about them, then felt embarrassed when they found out I was on them.
Most people I've found, are moderately interested, and ask about them. A handful admit to being on them themselves. A smaller minority still, are judgy. My mum was one such person, but I guess in fairness she has a greater interest than most in my wellbeing. Although she periodically worries about the long-term consequences, she has grown less hostile to the concept of them, the longer I've been on them successfully, with no side effects etc. She grudging now accepts that "they seem to have worked well for you". A couple of the women at work were a bit negative too, under the guise of "being concerned" for me. However, they've become more judgemental the better it's worked. On reflection, I think they were hoping something bad would happen to me, to prove what a "bad" idea it was. The petty side of me actually enjoys their frustration, now I've clocked what's actually going on 😶
So in summary (sorry for the essay!), I think lying is more hassle than it's worth. There might be a thread of people who started at the same time as you, who will no doubt be having these same concerns about now (try "Monjaro September 2025 Starters" or similar). Might be worth having a look for them x