Although apparently loads of people are 6s, it seems like not many are willing to admit to it (ie. on this forum), which can make the identification more difficult
I am fairly sure (though not positive) that I'm a 6. I have often been told that I come across as totally non-clingy...in fact, if anything I occasionally go too far in the opposite direction. But I think that this is because I am so afraid of seeming clingy and driving people away by it. There is a part of me, in my head and heart, that is really very clingy and even stalker-ish and obsessive with people I care about deeply, and it worries me that other people might pick up on that.
If I am worried that I may have offended you, and/or that you may be angry with me, it will disturb me terribly. I will need reassurance that everything is ok between us...but I won't necessarily push for that. I may just withdraw and construct paranoid scenarios in my head, until I hear from you and know for sure that all is ok. So, it's good with 6s to provide them with that type of reassurance and to go the extra mile in that regard if you think there is the slightest chance that they may be uncertain about the well-being of your relationship.
If I say something to you like "I hope you weren't annoyed about what I said the other day", it really translates as "I have a weird, paranoid and pretty much unfounded feeling that I may have hurt your feelings terribly by what I said and that it may have threatened the basis of our friendship - please reassure me that this isn't the case."
I'm not sure if that helps with your original query. Just a few thoughts.
lol! I totally relate on that.
One other aspect is that I constantly scan facial expressions and behavior about peoples I care about, and often worry if, inside, he's not blaming me for somthing wrong I've done, and sometimes push the person to speak out clearly what they think...but the most part of the time, there's nothing in paticular.
Actually, it amazes me that an ISTP would relate to me on this...you guys just seem really laid back and like you wouldn't stress too much about blips in your relationships with others? I'm probably over-simplifying?
ISTPs value their independance and are reserved around peoples, they also avoid confining commitments and are freedom-lovers, but thay can also love some peoples with an extreme intensity and be consumate loyal friend. 
Although apparently loads of people are 6s, it seems like not many are willing to admit to it (ie. on this forum), which can make the identification more difficult
I am fairly sure (though not positive) that I'm a 6. I have often been told that I come across as totally non-clingy...in fact, if anything I occasionally go too far in the opposite direction. But I think that this is because I am so afraid of seeming clingy and driving people away by it. There is a part of me, in my head and heart, that is really very clingy and even stalker-ish and obsessive with people I care about deeply, and it worries me that other people might pick up on that.
If I am worried that I may have offended you, and/or that you may be angry with me, it will disturb me terribly. I will need reassurance that everything is ok between us...but I won't necessarily push for that. I may just withdraw and construct paranoid scenarios in my head, until I hear from you and know for sure that all is ok. So, it's good with 6s to provide them with that type of reassurance and to go the extra mile in that regard if you think there is the slightest chance that they may be uncertain about the well-being of your relationship.
If I say something to you like "I hope you weren't annoyed about what I said the other day", it really translates as "I have a weird, paranoid and pretty much unfounded feeling that I may have hurt your feelings terribly by what I said and that it may have threatened the basis of our friendship - please reassure me that this isn't the case."
I'm not sure if that helps with your original query. Just a few thoughts.
Yes, it's an over simplification.
Well, I think ISTP 6 relate more on the constant ricochet of the type 6: they can be independant and detached from peoples, yet ready to try anything because they are devoted to someone or something. They see the world as inherently unpreductable and untrustable, so they prefer to count on their ability to analyze and improvize than on etablished plans and etablished norm, they think that they must be free to face life's difficulties, but if they find something or someone that they think fiable and reliable, they are loyal and happy. They are also more prone to the danger and adrenaline addiction side of the 6 . An ISTP 6 think it's above all important to be independent, despite we can feel insecure, they are distrusting and misgiving and don't exange their independence for their loyalty easily, while INFJs 6 assume more that they need support and guidance from others and that they need to be secure, not likely to be a loner wolf. So, yes, in that optic, ISTPs can be more counterphobic and INFJs more phobic.
Type 6 ISTPs may be Mel Gibson or Eminem, for example, or even Charles Gunn from Angel, Spike from BTVS, MacGyver, Amy Winehouse, Kristen Stewart or Malcolm X. Thoses are rather counterphobic, Woody Allen could be an example of phobic ISTP.
Type 6 INFJ seems more phobic, they are Helen Palmer for example, or Tara from BTVS, maybe also Daniel Jackson from Stargate SG-1. Susan Sarrandon would be an example of counterphobic type 6 INFJ.
I've been wavering a bit about whether I might be a 9 instead of a 6, but the cries of agreement from a few 6s here are making me think more and more that I definitely am a 6!
