The first key to maintaining a healthy relationship is communicating with your partner. Don't be afraid to ask what they want out of you. Instead of arguing, try talking things out and come to a compromise.Communication is a necessity to maintaining a healthy relationship. You need to talk things out with each other in a mature fashion.
Next you need to spend good quality time together. Go out to the movies, dinner, swimming, shopping, etc. As long as your doing it together it can really be anything. Show interest in each others hobbies and support each others interests. This will make both of you happier with one another.
A very important part of maintaining a healthy relationship is sex. By making love and being intimate with your partner you are showing them just how much you love them and appreciate them.Take your time and massage your partner slow and firm. Pay great attention to all of the parts of their body, showing every crevice attention. This is a great way to improve your sex life. You can also try different positions and role playing.
And the most important key factor is TRUST! If you don't have trust, you don't have a healthy relationship. You need to feel comfortable letting each other go to work, go out with friends, and so on. Trust is vital in a healthy relationship!!! You can gain one anothers trust by realizing that you love each other. Tell your partner that you love them frequently. Not that they have forgotten, its just nice to hear it once and a while.