I guess you have to take each situation on its own. Read the talk below by Elder Ballard. Although suicide is considered taking a life, just as killing someone else, there are or may be other circumstances. For example, someone who kills in a war, or in self defense is not under the same condemnation as someone who murders for gain. There are also things to consider under the specific reasons for taking of ones own life.
The link that Gaucho provided is excellent, you should check out the talks, specially the one of Elder Ballard. He quoted several Church leaders with regards to this issue, and he mentioned Elder Bruce R. Mc Conkie in the book Mormon Doctrine and he says :
Thanks for responding gaucho and LDS. I did go to the talk by elder Ballard, and it was very good. I also looked at some of the other talks. I don't know why I don't feel satisfied, I guess I just wish there more specific an answer, but I understand I'm not going to get that...we certainly can't say for sure where other people will go. I asked about this because I know of a bishop who once said that "the person would be in hell."
I think it is wise to trust your Bishop. It just isn't wise to think they are infallible. I believe you can trust them because they won't try to deceive you, but that doesn't mean they will always be right. The Bishop is entitled for inspiration for the Ward, but only your are entitled to inspiration for you personally. That is why we all receive the gift of the Holy Ghost. So, when your Bishop tells you something, you need to study it for yourself to see if it is true. Bishops also have opinions and personal adgendas.
I am confident the Lord doesn't judge and condemn us for just one act we might commit in our lives and ignore all others. Also, just as has already been said, we are judged by someone who has a complete understanding of the entire situation. Those of us in mortality don't have that same level of understanding, so how can we possibly judge anyone fairly?