Unlike the Magic Kingdom resort monorail, a gondola does not go through all of the stations in order, in a (vaguely) circular loop.
Except for arriving at Riviera station, you must get off at the end of the line. Then you may choose to take another gondola going the other way for a joyride, or, if you are at Caribbean Beach Station, take a gondola on a different line.
Riviera station is between Epcot and CBR, the latter two are ends of a line.
The other two lines are CBR to Hollywood Studios and CBR to Pop Century/Art of Animation (one end of line station shared by the last two resorts)..
Technically each line is a (n elongated) loop between its two end of line stations. For Riviera, gondolas going both ways between Epcot and CBR pick up and drop off there.