To answer your last question: "c) Could I go and just not drink?", I would say yes, you could go and not drink.
Whether you "should" or not, for "your" sake, this early in sobriety depends on how much it would be difficult for you. If at all, I"d keep declining, or suggest going out for lunch or coffee earlier in the day instead.
I don't have any trouble going out with friends who order drinks. I'll just order soda and lime.
If you were a pregnant woman, you wouldn't drink, but they wouldn't exclude you for that. If you were abstaining because of a medication or upcoming surgery, you could still join them.
I guess it depends on how focused on drinking the event is. If it's to a bar and they are going to get hammered, that's one thing: I would never go. But if it's just going to a nice cafe or restaurant where you could just as easily order a seltzer, or a dessert or appetizer, or even a cup of coffee, I think it's ok.
Others here may disagree with me! And maybe at only 35 days it's best to not. You certainly shouldn't ever let other people dictate whether you drink. That's within your control: The answer is always no. Eventually they'll learn you're a nondrinker. Just the way some people don't smoke, others don't eat fish, some like tea and never coffee, etc.
At my book club, my friends have started having fancy bottled flavored waters and seltzers and pretty glasses just for me.
Just my two cents!