marriage is just a commitment to someone you love.. if you truly would like to end up with that person all your life.. then go marry her/him...
marriage is a roller coaster ride.. sometimes your up there.. sometimes your down there... it's just a question whether at the middle of that ride, if you want to bail out or stick thru it...
Sooner or later, riding the roller coaster, would not be hell experience but rather a fun one.. it all depends on both the two of you... and with your soon to be child/children...