I'm jealous because I'm single.
Envious; feeling resentful or angered toward someone for a perceived advantage or success, material or otherwise.
Protective; zealously guarding; careful in the protection of something (or someone) one has or appreciates, especially one's spouse or lover.
Suspecting rivalry in love; troubled by worries that one might have been replaced in someone's affections; suspicious of a lover's or spouse's fidelity.
Suspecting, suspicious.