There is some gravity in space but its very weak. Gravity is the force that pulls you back to earth, or if you are near another big object like the moon, or the sun, it would pull you towards that too. When space travellers get far enough away from earth the pull of gravity is so weak they don't feel it any more.
If two people met in space there would be a small amount of gravity pulling them together ever so slowly. This is because everything has gravity not just planets and stars. The really big things (like our planet Earth) have much stronger gravity and so we feel it everyday.