My older girlfriend is getting broody... but I just want fun

I'm 27 and my girlfriend is 37, and we met back in January when she hired my firm to work on a project for her company.

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We started dating a few weeks later, once the project was over.

At first the age gap wasn't an issue. I liked that she was older and had more life experience.

But, over the past couple of months, all she's talked about is "the future". She keeps bringing up the subject of living together and wants to discuss where the relationship is going.

It seems a bit serious and it's stressing me out. She's even a bit weird about me going out with my uni mates or work friends without her.

Then last weekend, she went to her friend's baby shower and came home in tears, saying it really depressed her because she was nowhere near that point in her own life.