A wise Caleņa once listed some of the signs of a lady's true interest, including affection (holding hands, caresses, etc.) and regular communication (i.e., she'll do whatever it takes to stay in touch w/you).
Last year, I had what seemed like a promising relationship go south on me because of lack of communication on the lady's part. I met 3 ladies in Ctga. that I'd been talking with by phone for several weeks. They all had great personalities, but I chose the sexiest one. She claimed she was ready for marriage & that I was the one for her. But once I returned to the U.S., I had trouble reaching her by phone. She missed most of our phone dates, and Emailed me only about once a week. Busy w/her classes, she said. When I complained, she turned it on me & protested that I was not showing enough interest in her. Well, that relationship didn't last long.
I recently noted a similar pattern w/my Caleņa girlfriend. She's generally available by phone, but goes for a week or 2 sometimes w/o Emailing. When I expressed my desire for 50/50 communication, she admitted to being "disorganized" & getting "off track" (despistada) easily, & promised to write more. She also said she thinks about me a lot, & talks about me to her girlfriends constantly. I'm pleased with this response, but time will tell.
Sometimes it's difficult to distinguish a character defect such as being disorganized & forgetful (as I can be) with lack of interest. But either way, you have to decide what you need/want/will accept in a relationship.