OK, in Socionics you have these things called relationships and how they relate to other types. Sounds like a good idea right? Seems like there will be enough staples between commonalities between a particular type and how that type relates to other types right? Well I happen to think that Socionics is not at all all inclusive.
The main thing I want to say is that even if Socionics is true and true through and through there is something that it doesn't account for. That is the general attitude each person has toward the world. Now you might think this is covered pretty thoroughly based on Socionics theory, but the thing is individuals still have enough differences and variations that just because one type is suppose to get along with people of another type this is not exactly how it works.
Take LII for example. Its a type that goes based off logical inner systems which dictate how that individual thinks and acts, but it doesn't tell how that individual sees the world. I'd argue that the the thing that is dependent on how we see the world is largely based on a couple factors, but can be summed up to environment. So how does this work? So say you have a person who is naturally going to be an EII. Depending on how this person is treated through conditioning such as a pattern that is made apparent through the years growing up and as they come into adulthood this person has just as much chance at being an optimist as a pessimist. Let me explain as per example. One EII is treated like dirt as they grow up, abuse (emotional) runs rampant in the home and this person through nurture will have a low self esteem. Now take a person who was brought up in the rich 'burbs, had parents that actually knew how to parent correctly and this EII will have a much better opinion of themselves. This same concept holds true for any type. It doesn't even always need to be abuse or treated well to make an impact on how this person develops.
Depending on what people are exposed to has a great impact on how this person views the world through conditioning. So how does this tie into interrelating between types? Well it is simple really. Depending on how someone sees the world is going to have an effect on who they get along with. If two people who would normally, by Socionics theory not get along, but the way they see the world is largely the same based on what they have been exposed to in their life they might just be able to be really good friends. Same is true for people who would normally get along as far as types go, if what they have been exposed to in life is drastically different they may just not get along very well.