There's nothing wrong with being a stay at home mom. A lot of people would love to do so but they can't because they would struggle financially on just one income. Since you are now making your girlfriend's salary plus your own combined, her thinking was logical and reasonable by far. If she'd said, "I want to just quit my job and do nothing all day while you also pay buy me $800 concert tickets" it would have been another story all together. But she's saying she'd like to quit her job to devote her time to caring for your kids/home (therefore also saving on childcare costs, which are exorbitant honestly).

I can also understand how she wanted an inexpensive engagement ring before, and she's looking at pricier ones now since she knows that it's feasible with your salary. Some women demand the dreamier more expensive ring even if they know their boyfriend can't afford it. I can't even imagine how it would be a good idea to spend 15K on a ring, though, so you really need to sit down and have a heart-to-heart with her about the topic.

Def. not a gold digger type situation/nor an entitlement issue, but I can see how it could escalate in the future.