It's good to be tolerant of other people and their different opinions and beliefs.
In certain cases we know what is clearly the gospel outlook on an issue and what isn't. Either we know from what we have been taught or the spirit prompts us.
When we have a friend who uses their agency to follow a path that is clearly the wrong way, we can love them and even support them in a way that isn't condemning them.
But respecting other opinions isn't the same as accepting them.
Pres Monson addressed this on Monday when Peggy Strack asked if a member of the church can disagree with a church position (same gender marriage in this case) and stay in good standing. He said that it depends on what the position is and if it is apostacy.
Sadly there are times that no matter how hard we try to be accepting, the perception our friends have of us may be a reflection of our true beliefs. Some people will only accept us if we agree with them. We may try to reach out but sometimes for instance if we say "we love you," then vote for things like the marriage amendment, our efforts may be viewed as hypocrisy. Their view of us is based more on how the person feels about what we think and less on what we believe even if we haven't expressed it. In the end we do have to stand for what we believe.
There have been a lot of times when I've honesty tried, but have been told point blank "you say you accept me but there is no way you can be Mormon and believe that way and still accept me as a friend."
Ironically it is normally only Latter-day Saints who are struggling who say that. I think its because they know in their hearts what is true.
On the other hand I think its also possible in our attempts to be tolerant to go too far in the other direction and be confused with acceptance. True we need to accept our brothers and sisters, but if they are doing things we know are wrong then we need to be honest with them - if we are asked.
If we know we are weak ourselves we need to be careful of the influences we allow in our lives. Further if their actions encourage or normalize what would lead us to make a bad choice in our own lives we may need to step back.
I'm reminded of my friends mother's advice when she found out we were hanging out with some people who weren't making the best choices.
"You can be good friends, you may be the only example of a good choice they have. Just be careful it is you who is setting the example and not the other way around. Don't be led to places where you know that the Spirit isn't in your attempts to help them."
Yes there are different opinions and yes there is truth. There is also falsehoods that can comfort us into apostacy. And yes Satan is good at blurring "feeling" good with a spiritual confirmation if in our hearts we desire what is wrong.
It is sometimes easy to accept this as personal revelation and then accept it as truth. Worse if the person shares this with others who are struggling and they follow them than their is a real danger of becoming a false prophet even if our intentions are good.
They key here is that God will never guide us counter to His revealed truths. Personal revelation will only provide us with personal ways to follow the right path, not pave another.
There are also many different ways to follow the correct path and we need to be open to it and not stand as a roadblock to others who are on the right path. We also need to be careful that we don't confuse the ideas of man to be these routes and again the Spirit will serve as a guide to us if we are open to it.