I think a lot of people confuse the word "soulmate" with some idealized vision of what they want in another person or think they should have in a relationship, but that's not necessarily what soulmate implies. It's actually the person or persons who will challenge you the most to grow in life. Sometimes that can be accompanied by a wonderful relationship, but at other times, it can simply move you on to another place in your life, even to another relationship that is more compatible.
I don't believe there is only one soulmate for each person. There are several, in fact, and they don't necessarily have to be romantically connected.
I have met maybe two soulmates in the romantic area of my life, and did not chose to marry either one of them. However, I believe both men, in their own way, helped move me further on my path in life so that I could be ready for much healthier and rewarding relationships.
One man I was involved with for five years, and then remained friends with for an additional 13 years. The thing that attracted me to him was the fact that we could talk about anything and everything. Any subject at all, and we could talk about it for hours on end. And he had a wonderfully irreverent sense of humor. I felt very comfortable being in the world when I was with him. He was my best friend as well, which I think is extremely important. We shared a lot of the same interests and even similar neuroses at times. ;-)
I think it's generally important to have the same tastes and interests, but not necessarily for every little thing. For instance, even though I am a vegetarian and have been one all my life, I don't think I have ever been in a relationship with a fellow vegetarian. Also, it's nice if you can share the same sport activities, but not necessary. If they want to play golf while I ride horses, that's fine with me. As long as each person supports the other in their interests, I think that's all that matters. I think it would be horrible to be married to someone who didn't allow you to pursue what makes you happy in life (as long as it's not another person!).
The other soulmate I knew was not a very positive situation. Ever since I was a little kid, I would think about the man I would one day marry (just like all little girls do), and I would get both an image and the sense of a man who was older than me and who I thought lived in northern California (my family lived in southern California back then). As time wore on and I would tune into this man, I knew that he was married but did not have any children. Later, I somehow knew he had divorced. I was living in Colorado back then and somehow knew that he was still living in California. I also knew that it would be quite a number of years before we would meet. I don't know how, I just knew all of this. I felt like a homing pigeon, and I was steadily moving towards him as time went on.
I moved back to California and eventually went to work for his law firm, and that's how we finally met. One day at a firm picnic, the two of us were talking and it suddenly dawned on me that this was the man I had had a sense of my entire life. It really blew me away. And there was an immediate and intense attraction between us. We went out to lunch together, and when I was sitting in his car, I felt for the first time like I was "home." It was such a comfortable feeling being with him. And like my former boyfriend, he was a great conversationalist, with an irreverent sense of humor. Also, I learned his family was from Berkeley, he had been married before, but had divorced after 10 years, with no kids.
But he was always nervous around me so it was difficult to talk about anything too serious. Later, I realized it had more to do with the fact that he was a player and simply preferred small talk and games, which I detest and will not play. I also discovered that a lot of the rumors I had heard around the firm about him were true (that he was a womanizer). He not only made a lot of money as an attorney, but he came from old money. His family has buildings named after them. So I think he was used to getting his way because of that, even though he never waived it around and made a big deal out of it. In fact, I didn't even know all of that when I first met him.
Anyway, I think I am probably the only woman who has ever rejected him, who was not impressed by his money, and who did not allow his financial background to influence me, so I became a bit of a challenge to him. And due to our strong connection, he did not let go easily. So, for me, things went from "this man is 'the one'" to "
please don't let this be the one!" I didn't think I'd ever get rid of the guy either. He ended up stalking and harassing me for years afterwards. Just what I needed--a Sacramento attorney who pays other people to stalk and harass me.
Suffice it to say, he was definitely not "the one!!" But he was a soulmate who helped me move through a lot of personal issues in my past, using the backdrop of what I was experiencing with his abuse. Most of the people in the legal community know about how bad he is, but the general public does not. In fact, the last law firm I worked for was full of attorneys and staff who used to work for his firm years ago, so we were all old friends. The main partner's wife worked at the firm as a fellow paralegal, and she used to work as this guy's paralegal many years ago. So we compared notes, and she even knew about his stalking behavior. It appears I wasn't the only woman who he did that to. Anyway, I learned that not long after I ended things with him (actually, we never even got involved physically), a woman he was living with got pregnant on purpose just to get his money. He refused to marry her. She had twin boys, and he still refused to marry her. Finally, his grandmother threatened to cut him off from his inheritance if he did not "do the right thing" and marry the girl (not knowing she was a gold digger con artist), so he had to marry her. They proceeded to have the marriage from hell, and then divorced a few years ago. Some people thought it was a bit of poetic justice, considering how poorly he treated so many women, but I don't think I would ever wish something that awful on someone else, no matter what they have done to me. I'm just not like that. I think all relationships, good or bad, are learning experiences.
In retrospect, I think the reason there was such an intense attraction between us was so that I would not miss the valuable lessons I needed to learn from that situation. If there had not been such a strong attraction, I probably would have passed on the entire thing. Although, I have to say it did make me a bit gun-shy afterwards about the whole "soulmate" issue! The main thing to remember is that soulmate doesn't necessarily mean life partner. But they are probably the most important people you will meet in terms of how the relationship affects your life. Relationships are mirrors. The positive or negative qualities you react to in others are a reflection of the same qualities contained within you. Other people are a mirror for you to see yourself.
I think we all have to stay open to the people and relationships that have the potential to change our lives for the better--and that may not be our life partner. When I was young and agonizing over the lack of a relationship in my life, people used to try to comfort me by telling me, "There's a whole world of men out there." And all I could think was, Oh great, the man for me probably lives in Europe and I'll never meet him! (Typical teenage angst.) But these days with the internet, anything is possible, so I'm completely open to it!

However, I doubt I'll ever be fooled by the fairy tale "soulmate" thing again in terms of romantic relationships. ;-)
(Sorry if that's too long or too much info., but this is an area I have examined quite a bit in my life, for obvious reasons.)