I'm Dr. Jackie, an interpersonal communication researcher/professor and relationship counselor. And I just want to tell you that I don't really KNOW if you are doing ANYTHING wrong other than meeting the wrong people, which is true for most of us. Statistically speaking, if only a few people are right for us (some people believe there is only one special someone but I think realistically that we can be compatible with more than just one person), of course we meet many, many more people than those few. So numbers-wise, it could be that you just are meeting the wrong men.
Of course, that is easy for me to say. However, let's take a look at your strengths and your personality. Let's say you hold faithfulness and respect and truth and trustworthiness. very highly in a relationship. Well, there are a lot of men who may SAY they embody those qualities, but I think you'll agree that many men just do not follow THROUGH on these characteristics. And to be fair, we could likely say the same thing about women. It is one thing to "talk the talk" but another to "walk the walk" so to speak.
Now, let's list a few things according to research that help make a relationship last and simultaneously list some strategies for finding people with each. One is attitude similarity. If your basic core values and beliefs are similar, you have a better chance of having a lasting relationship. It's not so much "opposites attract"--I will mention that in another paragraph. But for the majority of people (there are always exceptions but I have to give you what the overwhelming general findings support), having someone with similar goals and beliefs is a strong foundation to a relationship. Now, where do you find someone like that? In a bar or club? It could happen. But if say you are religious, then maybe you need to do more ice cream socials ;-) or go to mass more often. If you are an animal lover, then maybe getting involved with the SPCA as a volunteer or help promote no-kill shelters on your day off...you will meet men who have similar values and ideals as you.
Also, people who share hobbies and interests often have higher levels of satisfaction as couples. I don't mean to say that you should spend every waking moment you are not at work with someone sharing hobbies or interests, but doing stuff together that you both like can really help grow a relationship. If you both like to garden or both like to cook--do those activities together.
Opposites attract is not usually true for core attitudes and beliefs, but it generally IS TRUE for personalities. That is, research findings show that couples who "balance" one another usually report higher levels of relationship satisfaction than couples who are both say "Type A" personalities. If one person is high strung and has workaholic tendencies, then that person's best dating partner would be someone who can help that person relax and do fun, interesting things. Likewise, a person who is "too laid back" and not very motivated could catch some enthusiasm from a more motivated, energetic person. So if you think you have met your soul mate, make sure you soul mate is NOT a copy of you.
Probably most important, you need to be able to communicate. Communication failure, and not cheating or money is actually the top reason people break up their relationships, although the other two are not far behind. But even when couples list "cheating," or "money mismanagement," etc., lack of communication is almost always a part of the problem. Two people need to be able to talk frankly and honestly and openly about money, about family, about goals for themselves. If you don't even know that your spouse does not want children and yet you want them very much, you should not marry that person. So the idea of being able to talk about anything and everything is so vital to the relationship.
I hope I have given you a place to start. Please let me know if I have helped you. If not, please allow me to try again--your satisfaction as a customer is my most important goal!