This page comprises about Sugar's relationships. Sugar has argued with a lot of people, but even though she seems mean, she has a golden heart for some people.
Diamond and Sugar have been enemies for a lot of times. In season 1 when they first meet, they hated each other. But ever since in Take A Hint, they have become best friends. Diamond is the only friend that Sugar actually cares about.
Their friendship has not survived much throughout the six seasons. In the sixth season, Diamond and Sugar became just friends after the incident that has happened. Sugar at first tried to bring out rivalry, before she realized that being enemies with Diamond again would only bring bad luck and being only friends would bring nothing.
Sugar and Diamond are nevertheless frenemies. Diamond has tried to make peace with Sugar but Sugar claims that they should be best frenemies. In Teenage Dreams, it appears that Sugar's best friend is Jewel. This might be caused from the season six incident as a continuity or that Sugar prefers Jewel better.
However, both Sugar and Diamond are best friends with Jewel and they both care for her and worry for her safety. As seen in Trapped In The Building, Sugar was the first person who gave a suggestion what to do to be the first persons to arrive in the warehouse, and if you look closely, Diamond smiled when Sugar gave the suggestion. When Jewel wanted to taste the laser, they both worry and stopped her together.
They have not get along quite well in the episodes, therefore no moments shall be added.
Throughout The Gems: A Magical Adventure, Jewel and Sugar are not enemies neither friends. But in Teenage Dreams, however, they are best friends. Sugar seems to be much passionate around Jewel, and Jewel (along with Riven) are the only persons she allow to touch her.
In The Perfect Spoiler, Jewel is first person which likes the idea of Sugar's play. Eventually Jewel also likes the prom which is also going to be held the same date and time. Jewel at first supports Sugar but then supports Diamond. She later does not have a decision and ran away. When Diamond and Avan find out Jewel was going to ask them a question, they told Jewel to talk to Sugar.
As Jewel approached Sugar, Sugar asked Jewel what she wanted. Jewel says she has a question. Sugar looks at Diamond and Avan who smirk together. She later calmly tells Jewel that Dexter would be the best date for her.