<human>: Can you succinctly summarize the text in 1-3 sentences?

I'm 29/m from the UK. I'm a few months out of a 7 year relationship that I left because I was unhappy and believe I've reflected on all the issues (if that's relevant). I'm looking to find women to date.

I work in a male dominated job and the only female friends I vaguely know are gfs of my male friends. I generally only meet girls in pubs/clubs (which is where I've met my past gfs), which I go to about once or twice a week. 

I've met quite a lot of girls recently this way. The usual thing that happens is that I'll approach someone I find attractive, we'll talk for about 1 hour, dance, kiss and then swap numbers at the end of the night, where I don't notice signs of them being uninterested in me (e.g. they'll ignore their friends to spend time with me, ask me lots of questions about me, be very flirty). 

However, the last 3 times, I've txted the girl I've met back and forth about 2 times over a few days then asked if they wanted to meet for drinks again on a specific date and the girl just stops txting back (I'm not sure why a polite "no" is so difficult for some people...). I'm very sure my txts aren't clingy or creepy.

I know this is all part of dating, but the mixed signals are really frustrating and I'm wondering if anyone has any insight into if I'm doing anything wrong and some tips to increase my chances? Is this to just be expected of clubs? I'm assuming that maybe they had too much to drink and reconsidered in the morning? I don't remember it being this difficult in the past as I used to get dates this way. 

Besides online dating, are there are only avenues I could look at for meeting women?
<bot>: I've been getting numbers from girls in bars/clubs but can't follow up with a date. Am I doing something wrong? Should I try other venues instead?