Hello, I'd like to help you with your question.
While it is certainly ok to decide to forgo relationships in your life, it does leave out an opportunity for you to meet someone and have a long term relationship. By making this decision without working through the loss of your former relationship, you risk isolating yourself from the chance at being happy with someone.
After a break up, it is very common to feel deeply hurt and even question yourself and what you might have done wrong to cause the ending of the relationship. When relationships end, there is a time of grief and mourning. You suffer a loss. And sometimes with a loss, it is easy to come to a conclusion that avoiding another loss just like it is easier than facing the risk of another relationship.
It can be that you still feel vulnerable about the ending of your marriage and this is causing you to question yourself. Before considering giving up a chance at another relationship, you may want to try working through your self confidence issues.
Start by acknowledging that the relationship ending was the cause of how you feel. You seem to have a lot of confidence in other areas of your life so you do have the ability to re build the confidence you need for a relationship.
Consider talking to a therapist about how you feel. By voicing your fears, concerns and lack of confidence about a new relationship, you can get the support you need to re build your confidence. Once you can do that, you are better equipped to re assess whether or not you want to try again with someone new.
You can also work on your relationship confidence at home. Here are some resources to help you get started:http://www.counselingcenter.illinois.edu/?page_id=191 http://www.mindtools.com/selfconf.html http://suite101.com/article/the-confidence-to-be-yourself-a12244
The Self-Esteem Workbook by Glenn R. Schiraldi
While it is perfectly fine if you ultimately decide to be single (and many people live happy lives doing so), rebuilding your self confidence with relationships can help you decide if being single is truly what you want to do.
I hope this has helped you,