Handling a suddenly protective dog

Since becoming pregnant, my mastiff/rotti/lab mix has slowly started getting more and more protective. I posted on here a couple months ago asking if any other fur mamas have experienced this, and received some great advice! It’s becoming more and more clear that she is being VERY protect towards me (and the baby) as time has gone on. We touched base with our vet, who knows what a happy-go-lucky, friendly dog she is, just letting him know she’s been getting more aggressive towards other dogs (even weary of new people) and he says he’s seen it happen quite often that the dogs protect the mom and growing baby.

So basically, in order to keep other dogs (and people safe) we’re going to limit her interactions when on walks and such.

For those seasoned fur baby mamas, should I just make sure I’m on opposite sides of the street, keep a muzzle on her, avoid letting her sniff and “say hi” to other dogs, let people know “she’s protective of me” when they ask to pet her? Maybe just avoid other people and pets all together? What’s the best way to approach things?

This is our first dog and baby. I’m so torn because she’s such a happy playful girl, but since this pregnancy, she can switch in a split second and snap at another dog and even growl and lunge. I just want her to be happy and worry that she’ll develop some bad social skills, or miss out on social time with other dogs that she used to love and thrive off of.