I'll bet I know exactly how you're feeling. For whatever reason, you've discovered something about the Church which has made you wonder if this really is the true Church, after all. You're just now beginning to wonder if there's somehow another explanation for all the good feelings you had while at church. After all you've learned about the Holy Ghost, you're wondering if maybe what you were feeling was just your emotions, or perhaps you're wondering if your fervent desire or need to believe caused you to receive the "witness of the Spirit" you had. You're probably also wondering if there's something wrong with you, since no other member of the Ward is struggling with their faith the same way you are. Everyone else seems to have successfully overcome any doubts they may have had long ago. Aside from this, of all the religions in the world, none offer a greater reward than Mormonism, right? The chance to become a God, progressing until all power and knowledge is achieved? This isn't a light promise. If Mormonism isn't true, what is? Better yet, after Mormonism, what other religion is worth belonging to?
The first and most important thing to remember is that there is nothing wrong with you. The fact that you're doubting doesn't mean you're being tempted by the Devil, it simply means that your brain is functioning the way it was meant to. God gave you your intellect, did He not? Remember the parable of the ten talents? With this in mind, why would God give you something He didn't intend for you to use?
Many, many Mormons have walked the same road you're currently travelling. Lots of others have undergone the exact same trials that you are undergoing right now, and I can almost unequivocally state that your current situation is temporary. You will reach a point, much sooner than you think, where you will be happy again. In most cases, you'll be truly happier and more content than you were before!
If you resolve your doubts and find your way back to full faith in Mormonism, then God bless you. Although personally that wasn't my destination, I fully realize that life is hard enough as it is, and each of us must do what we need to do to be happy, just so long as we hurt no one else in the process. If this is where your personal journey leads, then you'll be much stronger in the faith as a result, having underwent the "refiner's fire," so to speak. You'll be better able to meet the challenges that come with membership in a Church as demanding as this one. (At this point, you're probably wondering why the author of an anti-Mormon website can possibly have anything good to say about someone returning to full faith in the LDS Church. Although it is my opinion that the Church is false, and hence feel an obligation to help people realize this so their time and money can be spent on more productive activities, I am also fully aware that not everyone will agree with my conclusions. When another human being is suffering through a crisis, there's a point we reach when differences must be set aside and a helping hand extended.)
If, on the other hand, you come to the conclusion as I have that the Church of Jesus Christ of Latter-day Saints is false, again you won't be the only one who has done so. Not by a long shot. At the present time, you probably can't imagine how you or anyone else can possibly be happy again having once had a roadmap in life and an honest expectation of an afterlife. Again, believe it or not, you'll actually become happier than you were before. If you find another religion, you'll have an even better hope for salvation than you did before, since false religions save no souls. You may not believe this, but you'll be happier than before even if you become an Atheist, an Agnostic, or a Deist, for now you'll know that without any real guarantee of an afterlife, Heaven isn't something you sit around waiting to die to get into. If this life is all there is, then Heaven or Hell is here and now. Heaven or Hell is only what you make it to be here. With this in mind, you'll be far more motivated to get out and really experience life, to go out and do all those things you've wanted to do but have been putting off for so long. There's no greater motivator to live life to its fullest than when you think it might be a finite commodity!
Good enough, but now you're saying, "What about all those spiritual experiences I had? Weren't those revelations from God that the Church is true?" No, not by a long shot. Every religion has its spiritual experiences which are felt by its members. Feeling the Spirit or feeling the Holy Ghost is by no means unique to Mormonism. It's simply the Mormons who have a word for it and tout it around. I know I will offend a great many people when I say this, but remember the confirmation of the Spirit you had when you fasted longer than ever before and finally prayed to know if the Church was true? Well, in my opinion, the subconscious mind is a powerful thing. At the time, your body was starved for food, and your brain made you feel exactly what you wanted to feel so the body could finally get itself some food. Following these lines, I don't think it's an accident that Fast Sunday is held the same day as testimony meeting. When the members' bodies' defenses are lowered due to a lack of food, their subconscious minds are much more open to suggestion, generating spiritual experiences. (Hence also the overflowing of emotions that many of the members display while at the pulpit bearing their testimonies. I know you've seen this before.)
After all is said and done, where does this lead you? How will you be better off? Well, for one thing, you'll find that the weekend is actually two days off, not one (and you can stay up as late as you want on Saturday night!). You'll know that you're fine just the way you are, without all that guilt for not getting 100% home teaching. You'll realize that God probably doesn't care what kind of underwear you wear. You'll also find that every night is family night, because you won't have to worry about coordination meeting, Primary activity night, Young Men/Young Women's night, Relief Society homemaking night, Scouts, tithing settlement, your Bishop's interview, preparing your Sunday School lesson, and so on and so forth ad infinitum. Instead, you'll be fully enjoying all the extra quality time you'll be spending with your family doing what you all want to do. And with 10% more money to spend, you'll finally be able to take your kids to all those places they've wanted to go. If nothing else, you will know that you stayed honest and true to yourself, even when it would have been much easier to just give up and go back to church.
If you're wondering about how your friends and family will react if or when they discover your lack of belief, I have no clean-cut answers for you. Every family situation is unique. Remember, though, that any friend who would use something as superficial as religion to reject you isn't much of a friend to begin with. The same can probably be said about family members. And who knows? They might be more tolerant and accepting of your newfound status than you think!
The road ahead is hard, but from one who's walked it before you, trust me, it's well worth it! After all, who can put a price tag on the truth? Good luck!