Love (and hate) tritangles form in Daniel Deronda

Complications develop as the love-triangles form about 1/3 of the way through Daniel Deronoda, with Gwendolen agreeing to marry the totally worthless but worth-a-lot man, Grandcourt, a marriage she enters into with no enthusiasm, no desire other than to get access to his money to support her now-derelict family. But then DD shows up on the scene - not only as someone who'd been immediately attracted to G but also as a rival to a title - depending on whether his guardian will recognize him as a "legitimate" son - to which Grandcourt also has a claim. Right, it's impossible to keep all this straight, and you probably don't have to: the main point, suddenly G is flirting with this handsome guy and Grandcourt sulks and doesn't like this at all. Meanwhile, Grandcourt goes to see his former mistress, now living in a crappy house in dreary coal-mining town and raising her 3 (?) children - I think they're children by Grandcourt, though can't be sure - she hooked up w/ him after leaving an abusive marriage, I wish Eliot would say more about that - an important back story that she's leaving aside - and he demands back from her some diamonds he'd been holding: she insists she will return them, but only directly to Gwendolen. More trouble brewing? And for the 3rd triangle: What about the woman - the "jewess," Mirah - whom DD saved from drowning and has entrusted to the care of his best friend's (working-class) family? He is obviously drawn to her as well - so we'll have to see which force draws him more powerfully: the conventional but spoken for Gwendolen or the socially shocking but available Mirah.