Insin

Insin (noun):
a) A person who is involuntarily single, typically due to factors outside of their control, such as social, emotional, or situational challenges.

b) Like "incel" (involuntarily celibate), an "insin" wants to be in a romantic relationship but remains single despite their efforts, emphasizing the involuntary nature of their situation.

"Even though she’s outgoing and actively dating, Sarah often feels like an insin because she can’t seem to find the right connection."