How do I call what we are?

From my experience, when someone talks to you every night for three weeks and remembers how you take your tea, it means something. But I didn’t say nothing wrong when she asked why I haven’t called her ‘girlfriend’ yet. We met on this Russian site, not Tinder or whatever Americans use. She’s from Yekaterinburg, divorced, quiet like me. Her son doesn’t know about me. My mother already asks when I’m bringing her to dinner. She sends voice messages in the dark, talks about her day like she trusts me. I don’t know how to say that it scares me. Not because I don’t want it — I do — but because the last time I let myself want something, my wife left and took the apartment. We haven’t even met in person. But I feel something. I check my phone like a teenager. Is this a relationship? Or am I just lonely and calling it love? I don’t know when it became real. Maybe when she laughed at my terrible joke about Tolstoy. I don’t know what to do now.