Friend gets annoyed when we don't text all the time?? Advice Please

My friend and I used to be a lot closer when we first met. We're still friends and I have always been there for her and have gone out of my way to help her or give advice. Last year one time we went about a week without texting for no reason besides busy/life. She texted me saying things seem weird between us but I told her that nothing was wrong. Knowing her for awhile, I could tell by the way she texts that she seemed kinda annoyed. Since then, I feel that whenever we skip a day or a few texting she becomes different? I get the impression that she gets funny about it. Sometimes I feel obligated to text her something/a meme just to show I reach out so she won't think I'm being a bad friend. I feel that in her mind, not texting someone all the time means you don't care. What do you guys think?