Is it worse to be left on read or unread?

The gap means little on its own, so compare it to how she usually talks. Look at how long she typically takes to answer, whether she was the one to start threads, and how much effort went into her last few replies. A woman who usually answers within a day and suddenly goes quiet after a good plan is giving you a different signal than one who has always been slow and brief. Left on read after a normal exchange often means she got distracted or did not have a good answer ready. Unread for three or four days in a conversation that was already thin means the interest was probably never strong. Check whether the last thing you sent asked her something she could easily answer. If it was a statement or a question with no hook, the silence may be a reply to the message, not to you. Notice whether anything about your message required a decision from her, like a time or a yes or no. Those get skipped more often than you would expect.

A good follow-up after a gap leaves her an easy way in. Two or three kinds of message do this well. The first is a light callback to something specific from earlier, which shows you were paying attention and gives her something concrete to answer. The second is a small, specific question with an obvious answer, so replying takes five seconds. The third is a plain, relaxed check-in that does not mention the silence at all. A draft is working if she could reply with one word and still be fine. It should not mention that she has not replied, what she should do, or how long it has been. Leave out apologies, guilt, questions about whether she is still interested, and any reference to other messages you sent. Keep it shorter than your original message, because a long follow-up after silence reads as anxious.

Send the follow-up once, and do it at a normal time of day rather than late at night, when a message looks more like a need than an invitation. Wait at least a day or two after the last message before following up, and longer if the conversation was already slow. If she answers, match her energy and let the conversation find its own pace. If she does not answer, leave it. One unanswered follow-up is a clear enough answer, and a second one tends to make the situation worse, because it adds pressure to something she has already chosen not to pick up. If you have had a few days and a single follow-up with no reply, stop texting her about it. Do not send a final-message speech or a passive-aggressive sign-off. Let the thread sit, and move your attention to other people. If she comes back later with a normal message, you can respond normally, without making her explain the gap.