How can I get a girlfriend in Hualien?

I’m new to Hualien. Compared to other places in Taiwan, Hualien life is dull. Is there any night clubs in Hualien?

No clubs.
A few bars.

There’s a place out on Zhongshan Rd opposite the Sports Stadium that does live music most weekends. Worth checking out, though I’ve not been for a while.
Around about here https://maps.google.com/maps?q=taiwan+hualien&ll=24.005028,121.587598&spn=0.003077,0.005037&oe=utf-8&client=firefox-a&hnear=Hualien+County,+Taiwan&t=m&z=18&layer=c&cbll=24.004898,121.587699&panoid=bnSdmfIOxfwmwOR_tHHtYQ&cbp=12,54.75,0,0

Further afield and in termtime, you might want to try hanging out in the bars/eateries down at DongHua University. That’s a 30 minute drive south of town, mind.
e.g. https://www.facebook.com/9803cafe/info