You know Starbuck, from the re-envisioned Battlestar Galactica? Like that, though not necessarily so damaged.
Right now one of my closest friends is an ISTP. She's vivacious, goofy, optimistic -- ready to take anyone at face value, and sit and listen and nod, then offer an objective view of what they need to do to improve their situation, based in her own experience. A perfect bartender. Which makes sense, as she works in a cafe now and has bartended before.
She loves to do stuff -- to snowboard and ride motorcycles and play tennis, and is quick to invite anyone along for the ride. What you'll never get her to do is stick to a plan. You can intend to go somewhere with her in the afternoon, and unless you stay physically beside her, she'll forget all about your plans together and will go off on whatever whim strikes her. Not out of carelessness, and it's not a snub; it's just the way she is.
Anything that's in front of her, though, might as well be the only thing that exists. Which is great, if you're the thing in front of her!
She's very bright, but not particularly intellectual. It's more based in keen observation and practical experience. She's empathetic, but fairly detached. "It's all okay" might as well be her motto.
Right now she's in a relationship with a clingy, broken ISFP dude. She loves him, but she's beyond her patience. She feels like it's not her right to just go dump the guy, so she is waiting for a solid reason to break up with him. I think he's presented several, but at the last minute she keeps backing out, and -- weirdly -- conceding to even tighter demands from him. As if he had any ground to stand on.
The other day I got an IM from her while I was napping. I woke about an hour later and called her. This was maybe seven in the evening. She answered with a whisper, and said she couldn't talk because her boyfriend was asleep, but she'd get on the computer.
The situation was, he had been asleep all day, on the floor, in the middle of the studio apartment they share. She wasn't allowed to leave the apartment without him, and wasn't allowed to speak on the phone with anyone when she was with him. She couldn't make any noise, lest she wake him. She couldn't turn on any lights, lest she wake him. She had made dinner for him, and he refused to eat it and went back to sleep.
She was wishing, idly, that she could go to a restaurant around the corner. As if it were a nice, but impossible, dream. I suggested she go, decompress, get something cheap. Leave her boyfriend a note, so he felt like he was in the loop. Just get out of the situation, for an hour at least. She shrugged, so we talked about penny farthings and mustaches for a while.
Eventually her boyfriend woke up and found our chat log. She got in big trouble for talking to someone behind his back. Her response? The equivalent of "yes, dear", and then deleting the chat client. The next day I suggested that she wasn't actually solving any problems here, and she shrugged. Well, whatever. He wasn't there at the moment, so the topic was too abstract to worry about.