You need to firstly ask yourself whether he was a twin flame or a soulmate. There is a big difference.
Firstly a soul mate is a mate of one's soul, someone you share a connection with such as a boyfriend/girlfriend/husband/wife/friend, even a pet.
A twin flame is the other half of your soul. Before this one soul incarnated it was split into two separate souls and became two separate people, usually a male and female. Some believe that twin souls do not exist but I guess it's up to each individual to judge for themselves. Now it is said that twin flames/souls usually do not incarnate in the same lifetime together unless they are both here for a very special purpose to fullfill together, usually a spiritual mission of some sort. A twin flame reunion is divinely orchestrated, it is not forced or controlled. That person is almost a mirror image of yourself and if you are not ready within yourself for that intensity, you should not pursue it.
In some twin flame reunions there is usually one person that wants to pursue the relationship and the other avoids it, the one that avoids it is known as the "runner" in other words they are not ready for the intensity that this relationship could represent as it is the ultimate relationship that transcends all others.
If in this situation and there are difficulties between the both of you, for example he is already in a relationship but is choosing not to leave, then you have done the right thing to leave it alone, he must learn his own lessons in his own time, that is if he is in fact your twin flame, only you will know.
Twin flames are meant to be together when they both are at the point in their lives where they feel they no longer need partners and are at the point of self fullfillment in their lives, this usually happens in their last lifetime together. It is destined to happen eventually as it is meant to be from the Divine (God) but it must happen in it's own time when BOTH people are ready and not just one.
I think you have done the right thing to leave the relationship alone. If he truly is your twin flame the reunion will happen in it's own time and this does not mean for you to sit there and wait for him until you grow old. You must get on with your life, enjoy other people's company and be the best you can be as a person. What is meant to be will be, have faith in the Divine (GOD) as he knows what he's doing with these sorts of things.
Hope this is of some help.