How we cite our quotes:
"Why did you marry again, mamma? It would have been nicer if you had not."
Mrs. Davilow coloured deeply, a slight convulsive movement passed over her face, and straightway shutting up the memorials she said, with a violence quite unusual in her—
"You have no feeling, child!"
Gwendolen, who was fond of her mamma, felt hurt and ashamed, and had never since dared to ask a question about her father. (3.5-8)
Gwendolen doesn't learn this until later, but sometimes people marry for reasons other than love. We get the vibe that Mrs. Davilow didn't really want to marry her second husband, but may have done so to help Gwendolen.
"Well, what is the use of my being charming, if it is to end in my being dull and not minding anything? Is that what marriage always comes to?"
"No, child, certainly not. Marriage is the only happy state for a woman, as I trust you will prove." (3. 41-42)
Oh man. Mrs. Davilow seems to think she's comforting Gwendolen and telling her that marriage isn't so bad, but jeez – it's kind of depressing to say that it's the only happy way for a woman to live!
"My dear Nancy, one must look at things from every point of view. This girl is really worth some expense: you don't often see her equal. She ought to make a first-rate marriage, and I should not be doing my duty if I spared my trouble in helping her forward. You know yourself she has been under a disadvantage with such a father-in-law, and a second family, keeping her always in the shade. I feel for the girl. And I should like your sister and her family now to have the benefit of your having married rather a better specimen of our kind than she did." (3.92)
Mr. Gascoigne is willing to spoil Gwendolen because, so to speak, he expects a good term on this investment. That is to say, he figures by spending money on Gwendolen, it'll be easier for her to make a "match" that's good for her family.