Green’s Dictionary of Slang

stella dallas n.

[film title Stella Dallas (1937), a celebrated tear-jerker starring Barbara Stanwyck; an earlier silent version (with Ronald Coleman and Belle Bennett) was released in 1925]

(camp gay) a loser, an unfortunate.

[US]B. Rodgers Queens’ Vernacular.
[UK]J. Hayes ‘Gayspeak’ Quarterly Journal Speech LXI 256–66: A melodramatic loser [...] is a Stella Dallas. A man who is suspected of actually enjoying his constant misfortune becomes a Camille or a Sarah Bernhardt.