Are you treading water? I mean, is it hard to breathe in your relationship? There are some things that you must ask yourself. Treading water in any relationship can be a horrible experience to all parties involved. Evaluate your life and answer these questions?
Are we friends? I know this SEEMS like a no brainer, but you will be surprised by how many people can say no to this. They get into these "situationships" and do not realize that they ARE NOT friends. They have no common interested, no things that bond them together. Just Sex. Not even real feelings. Just more like jealousy because you THINK that person belongs to you. It is a forced situation that will have no life shortly.
How long have I been with this person? Ok, there are many factors that are in this question, like how long do we consider us a couple? If you were friends first (see number 1), how long did it take to have "the talk" and know that you were an exclusive item? If you are carrying this into years and you want something different AND it has been expressed, you might want to think about what your next steps are as a couple. Remember, time waits for no man... (or woman).
Do you see a future with this person? Do you see you married? With a family and home? If you do not, you might be comfortable in the situation, and need to think about your future. If you do not see yourself with a person until you die, you need to get out. Quickly.
What is his or her timeline? Does it match yours? While you may say that you have a future with the person that you are with? Are you ok with what they think is an acceptable time to go to the next step? If it doesn't line up, you might want to rethink the timelines and have another talk.
Do you REALLY want to be there? Sometimes, it is out of convenience that you are with a person. Nothing else better to do. You get benefits by being with a person. If you really don't want to be there, get out. It is not fair to ANYONE...including yourself because you are not happy...Happiness is what every relationship should be. A safe haven for you and your heart.