<human>: Forgive me for my mistakes, english is not my first language.

To start off, I'll add some back ground information. I started dating my husband[38] when he was 34, four years ago. It wasn't until it was a year into our relationship that I met his daughters, twins, from his previous marriage. They were only 11 at the time and still in secondary school and my husband only had custody of them on the weekends so I only saw them every so often, but we got along fantastically and I adored them. This relationship continued until they were thirteen and their father and I got engaged. I decided I wanted more future step-mother/daughter times so I set up "dates". I would take them shopping, for hair appointments, nail appointments, a spa weekend etc. so we would get to know each other and to be honest, I was terrified of becoming the "evil step-mother" in their eyes so I tried really hard to get them to like me.
I make a comfortable living so I spoiled them a bit during these trips, but they seemed to love being around me so I continued to do so up until my husband and I's wedding. 

The current problem:

The shopping dates never stopped after I married their father, I enjoy them as much as the girls do and I love being able to buy them things. But my husband thinks they've started to take advantage of me. The things they are asking me to buy are more and more expensive with each trip, and they want more. One of my stepdaughters wanted me to book her a $750 hair appointment the other day for her birthday, now I have the money and would of done so but my husband says that is a ridiculous amount of money to spend on a single appointment and that I will have to think of something else for her birthday. Her sister isn't any better and is requesting a 3,000 dollar handbag for her birthday from me. I think I have made a huge mistake by spoiling these girls, and my husband has drawn a line and made me see the my mistakes. I don't know what to do now.

Can you condense the text into a few key points?
<bot>: I've spoiled my stepdaughters and now they have extreme expectations. My husband say's its too much and I don't know what to do.