Is sending a letter creepy in this case?

Anonymous
Brief scenario: I've been friends with this girl for about six months, but we both wanted to pursue something beyond that, so we went out a few times. Everything was fine, but a week later, she apparently started to have some personal issues. She gets overwhelmed easily, and the last I spoke to her was a month ago when she apologized for not having been around but was dealing with a lot. I've sent her a few texts and tried calling once in that month's time, but she never replies. Basically, the status of whether or not we're just friends or more is up in the air.

Would sending a letter to her home just saying that I was thinking about her and her family and hoping that everything was getting better be out of the question? Something saying that I've really valued our friendship this year, and I'm not sure if there's any interest beyond that right now, but that I hope there's still a place for me in her life, and if she wants to talk, to know that I'm here (basically, a respectful letter). Would this come off as creepy or weird? I feel it's a bit more personal than an e-mail or text, and I'm really not sure if a phone call is open since she never replied back from a voicemail I left two weeks back. I'd say since we were friends, it's fine, but she just gave me her address the last time I saw her so that I could pick her up at her house, so I've only been there once, so I'm not sure if this is violating a confidence.

The other thing is that there is a decent age difference (30 for me, 21 for her). I've never been married or had any kids, so I guess it's a "young" 30, but that didn't seem to bother her as she's known my age for a while (I've never dated someone with this much difference in age). She lives with her mom, and I know her mom had some reservations because "older guys only want one thing" and she'd want to meet me if things got more serious. I had no problem with this.

Anyway, a letter...Creepy? Fine? If it's a bad idea, anyone have a better idea I could use?
Is sending a letter creepy in this case?
2 Opinion