Protective, yes. Jealous, no.
On the family side of things, well, it's family. I was raised with a great one, so I'm obviously going to feel inclined to defend them. I ask my sister every now and then if they're okay, I help my parents out if I can, etc. As for jealousy, I don't really have much to be jealous about. I'm the oldest child, and as much as I hate to say it, I've done rather well in life in my parents' eyes. Reason I hate it is cause it casts a shadow over my two younger sisters. That's not something I imagine to be very pleasant.
As for friends, same thing. If they really are my friends, then that means I care about them a lot, and I'm not gonna watch them just watch them fall into the wayside. And I don't really have much to be jealous over. Perhaps talent, but that's a trivial subject. And it's not something I really even focus on. I don't strive to be just like my friends, that's not why I have them around. I keep them around because they're people that matter to be because of who they are.
As for my girlfriend, once again, same thing. She's someone I really care for, so being protective is something that'd just come naturally. Not to the point where it's like "Dipu, that's a little kitten, it's not going to maul me to death", but a reasonable amount. =P And jealously can be tricky in a relationship, I guess. I'm not jealous, but I'm finding out very fast that there are little things that a person can take to mean a whole lot, and thankfully, I'm smart enough to realize that. D: