Support/problems with friends

Hey guys, I just need someone to listen to my rambling and maybe give me some advice if you can. I lost my dad very suddenly and unexpected in December, he was 59. I have not felt the same since then, and I kind of have trouble acting normal around people/friends.

One of my friends reached out to me, she was actually there at the funeral (since she knew him and wanted to pay her respects) and we met the week after his death. During our little meeting she didn't really talk about it and didn't respond much to things I said about my dad. After that, we only texted a few times about really mundane things, until I sent her a really depressed message about how I feel about his death, to what she answered if we want to meet up again. I don't live in my hometown anymore and only come to visit my mom on weekends, so I actually couldn't see her and I also didn't feel like it, since the last time we met, it felt like she was kind of avoiding the topic, even if I wanted to talk about it.

So long story short, I didn't answer, to another message of hers I still didn't answer (I'm not sure why tbh). It was my birthday yesterday and she sent her congrats, I was planning to answer today, but instead she texted me a really long message saying: how she knows she can't possibly understand how I feel and that she wants to help me, but she doesn't know how and that me not responding makes her wonder if she did something wrong. And it makes her question our friendship. And that she hopes that I have friends that are supporting me.

The message started of so nice and understanding, but the last two points made me really sad. I understand that it's hard to navigate around someone grieving, and I myself don't know how to handle it yet, but in a nutshell, I feel like her message is not quite fair to me

I'm really unsure how to respond to her text. Not answering is not an option obviously, but I am really hesitating cause I don't know what to tell her...