My ideology is, most times, that I will, and do, respect those who do NOT seek to force their beliefs upon, HOWEVER, cross the line, start preaching and you will receive as good as you give and if not, then even better.

I tend to mirror them. If they don't bring it up, I don't bring it up. If they are polite, I am polite. If they are dismissive, I am dismissive. And so forth.

Here's a thought for self-reflection: what if I'm not as innocent as I think? What if, sometimes, I am the one who starts the conversation? What if my dismissive tone elicits an attack from them? I am not a paragon of virtue - sometimes I'm a jerk.

I think that I'm mostly okay with that. I usually behave, and some lively conversations have begun when I haven't. Most of them are probably the same way.

The tipping point for me is when they expect me to respect their belief but they do not respect my disbelief or get mad if I point out facts.  I don't try to convince any of them to leave their religion or convert any of them to using science and logic.  They are worried for my soul, that I am going to go to hell, and they start trying to proselytize me.  I am never the one to bring up religion in a conversation, usually they are the ones asking what church do you go to, etc.  

My MIL is an old school catholic raised along the Arizona border.  Apparently they like to keep their people in the dark.  I was talking with one of my SILs about one of Dan Brown's books - think it was the DaVinci Code.  My MIL didn't like the ideas in the book that he didn't die, left and went to France, was married, etc. (Let me just say that I have never seen any proof that Jesus existed as a historical figure, but we were talking about it as if he was.)  I made a comment that as a Jewish Rabbi it would have been very unusual that he wasn't married in his 30s.  My MIL didn't know that he was a Jewish Rabbi - she thought he was born a Christian.  She got so upset she started crying...everyone blamed me.  It's my fault for discussing how a possible historical figure may have lived 2000 years ago?  Why don't you blame her priest who has kept her in the dark?!  A few days later she said she was sorry for the way she reacted and that she wanted to learn more.  But out relationship has never been quite the same. 

I am  no longer close with my SIL either.  Last time we were over at my MILs house she made a comment (while my MIL was out of the room) that MIL was worried about my husband because he might not believe in god.  I felt like that barb was directed at me since they all know I'm an atheist.  Suddenly 18 years later she's worried?  BS! If she is so concerned then why doesn't she speak to my husband about it.  This SIL always likes to stir the pot and isn't happy unless she's fightening with some family member.  My husband has never called himself an atheist or an agnostic - he says he's spiritual (he's never had a problem with being an atheist and he doesn't care enough about religion to discuss it). But he has told me when his time comes do not left them do any kind of religious stuff at his funeral.

Respect is earned.
All humans deserve a base amount of respect as a human, beyond that respect is earned.

An erroneous belief is not an negative action on its own, and each human, believer or not, stacks both up inevitably.

noun

1. a feeling of deep admiration for someone or something elicited by their abilities, qualities, or achievements:
   OR

2. due regard for the feelings, wishes, rights, or traditions of others:
   OR
   verb

3. admire (someone or something) deeply, as a result of their abilities, qualities, or achievements:

How do you mean Respect, how are you using that term?
AND
How do you mean Contempt?
a: the act of despising : the state of mind of one who despises : DISDAIN
glared at him in contempt
OR
b: lack of respect, disrespect

I, personally, try hard not to DESPISE humans. We are a stupid lot of ignorant primates with violent weapons and destructive tools who think we are smart . . .so we all fuck up and make poor decisions. Who am I to DESPISE another because they reached a conclusion I find distasteful or illogical or even one for which I hold no respect?

It is a case by case basis, not a block demographic prejudace, that is what many religions do themselves. Include or disinclude to their tribe. I try to see my tribe as humanity.

I believe all people deserve respect, people's ideas - when they go against reality itself - not so much.

People, who give respect, deserve respect whether or not you agree with their choices and opinions. That being said their religions deserve no respect. I have yet to see a religious person say, Wow, great you are an atheist, so they get the same back from me as they gave me.

Rights of belief and 'worship' are due respect. To distract and insult others in attempts to propagate beliefs or to use them as an excuse to push punitive laws imposing behaviors prohibited within those beliefs should be punishable with fines. It should also mean loss of tax exempt status.

I think a tipping point is when those believers that know and admit what a belief is and does not get irritated at criticism, compared to those that like to preach death chants. That point of a moderate religionist that keeps quiet when they know some of the inequalities and perpetrating violence going on. A blind eye....

Abortion is used by the right to control women! Why are not men held accountable for getting the woman pregnant who had the abortion! I need some answers! You never hear of the man who got the woman pregnant who had an abortion! Why is that???? The NRA!

RE: My question: Where on that spectrum is the tipping point, and why?

1. When they meddle in governmental affairs, eg forced school prayer, tax money to promote religion, anti-LGBT policies and such,

2. When they knock on my door and interrupt my dinner hour so they can read the Book of Mormon to me, or something analogous,

3. Cults like Scientology, Moonies, et. al., who actively seek to harm people for their own ends

When they try to run my life

Everyone should be respected... If they are respectful... Just because they believe in something you don't, does not justify not respecting them... Would you disrespect a child for believing in Santa clause? Or that daddy or mommy are the greatest of all?

Just enough to get them to become agnostics!