I think I understand what you're saying about how you feel. It's not irrational - as you suggested earlier 'someone gets along better with people who think the same way' - hardly surprising. What it seems to me is that the cause of your concern is that you are afraid you'll have to censor what you say because you might inadvertently cause offence.
To this I would suggest that a) if offence is ever given, inadvertently or not, simply apologise and get on with things. If people are going to get so caught up about a misunderstanding then friendships are unlikely to last anyway
and b) that perhaps your concern about inadvertently offending them is because you hold views around those who have faith that you think, deep down, are offensive to them? For whatever reason - i'm not looking to cast stones. There shouldn't be a fear of letting it all hang out, unless you think that there's something to hang out which might offend a particular section of people?
If this is the case, can I offer you a hopefully more nuanced view that might help you to understand and at least approach things that might mean you are not worried about offending? That said, people on both sides of the debate generally require a thicker skin...
Distinguish immediately between what someone believes as given to them by whichever religion they attend, and belief in God in general. (Please keep in mind that what I am saying here, I say as a Catholic so i'm not dismissive of what a religion teaches!) . This is often referred to as a distinction between 'natural theology' and 'revealed theology'. If you have a problem with revealed theology, then for the sake of brevity, I would suggest either choosing to think 'that's something I don't understand and therefore will not engage with, but can respect another person's choice to engage with it' or doing a TREMENDOUS amount of study in order to understand it better. It is, unfortunately, not as simple as reading the Bible. It is also no accident that there are whole libraries filled with discussion on the subject of revealed theology; precisely because it is a very simple subject :D
If you have a problem with natural theology, or a belief in god as such (which from some of your previous posts it did appear to be, although it did seem to cut both ways at some point), perhaps you could think of it in this way:
In science (and I would argue in general terms of human thinking), we take a set of data, and extrapolate principles from that. Hypotheses about this principle are proposed and tested again, and again, (hopefully) producing the same results, until we have what we believe is very well confirmed and confidently believed principle about some such facet of the universe. I think, and I believe I am reasonable in thinking such! that human beings not only do this in science, but do this in every day life, and that the set of data that humans deal with is every day experience. And every day experience teaches us that nothing comes from nothing - we do not ever expect to find any kind of pattern or intelligible experience without expecting to find some kind of intelligible cause to that pattern or experience. This is, I would argue, the basis of any kind of scientific experiment at all - seeking to understand the underlying principles that explain an apparently ordered and coherent set of experiences.
Following that pattern to regress and regress, we can work down to the subatomic or down to the nano-seconds post-big-bang, and what we can find, again and again, are layers of principles in either physics and chemistry and so on that can give plausible and (hopefully!) disprovable theories that can then be tested so as to give another layer of explanation as to why things have happened.
However, that pattern, continuing ad-infinitum, does not ever resolve itself; no observable principle is self-explaining, evolution explains changes but does not explain itself, biology may be explained by chemistry, chemistry may be explained by physics, but physics does not explain itself, so we must, EVENTUALLY, come to a point when we are faced with a question: is there a principle that IS self-explanatory? Is there a principle that answers the question 'buy why should that be the case?'.
Even with the most far-flung theories based on the anthropic principle, based on all sorts of theoretical physics about potential universes and multiple worlds theories, the question of 'but why should that exist at all' persists. We can have many different theories that explain why our universe or reality should be so, but if we create ever-greater worlds or universes or principles to explain it, are we not simply left with the question; but why this or that principle?
So, even if you disagree with the conclusion that others might come to, can you consider that it is not unreasonable for people to think that there is a self-justifying principle that explains both itself and the natural order? To think that such a principle might be astronomically complicated and radically simple? And, most importantly, to think that even if you are not convinced by the reality of such a principle, it is not irrational for others to think that something like that might exist? That it's existence will never be able to be explained in terms of science or observation, but that the entire ordered nature of reality does beg some kind of explanation, and that even if you find this principle unsatisfying, you can understand why others might find it satisfying? If you think this, then perhaps you will have less fear of offending others because it's simply a different point of view on a question about which you disagree, but can accept that others find the other side of the argument more convincing?
Anthony Flew's book 'There is a God' should helpfully explain more elegantly the point I am trying to make :)
If i've gotten it completely wrong then I apologise for the interminable post!