Is she interested or no ( Read below)?

I have a coworker that i think likes me. She is older than me (10 years).
Since last year she has been acting suspicious we have had some tense interactions. She was sending me text messages and I was starting to suspect so I invited her out since my female friends at work told me that i should because they also suspect that she likes me.
We went out but nothing special happened.
She sends me messages once in a while but not to often ( like a month or 2).
So what's her deal? Because every time I say to myself " maybe she was just being friendly or change her mind" she talks to me again or something happens at work and my coworkers tell me that she seems to like me.
Is she interested or no ( Read below)?
Post Opinion