I would say INFP recluses when processing. My husband always needs to talk and talk when he is processing or stressed and it is stressful at times for me because when I need to process I need to be quiet. Even things like car repairs, he wants to talk every detail out with me, says that is the only way he can really think about it.
I would say INFP needs more sentimental emotion and cuddling and stuff like that. But on first glance INFJ will seem warmer and more needy and more open, but as time passes and INFP opens fully, its INFP who wants more emotion from SO and close friends.
This is pretty interesting, as I can relate much more to your description of INFP than that of your husband -- but I think I'm quite introverted and I've never been one to talk much or chatter.
I definitely need a LOT of time to myself to process. I don't talk when I get stressed, I need to be alone to sort through how I feel, and what I think about something. I can't really think about stuff/figure things out while talking. So it's going inwards first, contemplating/processing, connecting the dots or reaching resolution, and THEN I feel comfortable talking about it, just to let it out, or simply share it, or to get feedback or affirmation. But if I think on my own for a while, and really can't figure anything out, I might then talk to others because I recognize I need input, or need a sounding board. But that's only the second step, once I realize I'm getting nowhere on my own. These sorts of things can get complicated -- complicated to know the root cause behind why I go inward, I mean, and don't talk things through with others. I've always been rather solitary, and I think it's just old habit started from long ago when I never talked to anyone about anything personal, and kept it all in. It's only in the past 3-4 yrs that I've really worked on opening up and being more expressive with others, and actually extroverting my inner world.
I don't really know any confirmed INFP's, so I cannot compare myself to them. I am good friends with several INFJ's, though, and I have a lot of similarities with them. It's interesting, though, because although they're all INFJ's, they do have different nuances -- I mean, there's definitely a spectrum, and variance within each type. One of them is so talkative and emotionally expressive that she rather exhausts me sometimes ;-), a few are more talkative than I but definitely have more balance in talking vs. listening, and are more cautious and reserved in expressing emotion, and the male INFJ I know is pretty similar to me, as far as his introvertedness goes. And then a few are what I would consider much stronger 'J's' than I. I've never really felt my 'J' tendencies are terribly strong, but maybe that's just where I'm at now, and maturity. I don't know. Also, I'm just...not as reactive/combustible (for lack of better words) as one, and not as planned as another.
Oh..and I have never really had a life plan. ;-) I don't think that can be tied to J/P. One of the INFJ's I know has always had a life plan, and she's one who has a lot of direction (compared to I). The other INFJ's I know are more floaty, like me, in that way.
But..while several people have confirmed my INFJ-ness and I don't think I'm nearly as mellow, in general, as the INxP's, I do think my Fi is pretty high, and is probably as strong as Fe. So there's that too.