How should I respond when left on read?

This year, I resolved to socialize more with my classmates in grad school. I already had a “clique,” but I admired my classmates so much and I wanted to know more about others better! So at an informal social event for the students, I chatted with classmates. I suggested hanging out at some point. All seemed amicable, and most have followed through since then. The issue I have is with the two who did not. The next day, through text, I asked whether they’d like to hang out next weekend. They said they were visiting family that weekend — totally fine. But they, individually, ignored follow up texts to hang out this weekend.

This is the first time I’ve sent a text, and the recipient seemed to ignore me. (I’m not certain both left me on read since SMS has no seen or unseen indicator. But it’s unlikely that neither have seen the message.) I feel snubbed. Whenever I think about them, I sneer and think, “These cowards couldn’t even be straight with me.” But I’m sure this isn’t a healthy response. Shunting hatred at someone for a perceived slight feels like a poor coping mechanism. But I don’t really know how to react to this in a healthy productive manner. I’ve never dealt with this before.

Of course, I understand one obvious solution is to confront them. Let’s call one A and the other B. A is a man and B is a woman. First, I’m ok asking A in person if we find ourselves next to one another at some point. However, I’d still like some advice with how to approach this, emotionally, in the meantime. Second, as a man, I’m a little reticent about B. I hear about men who can’t take no for an answer, and persist zealously. I don’t want to so much as appear like that person. Third, for both A and B, I want to respect their wishes if neither wants to hang out. It’s no issue! If either wanted to hang out, wouldn’t they follow up? So I’m also entertaining the notion of not asking in person at all. Just let it lie. I just wish they were straight with me.

Whatever the case, I’d appreciate thoughts from people who have experienced being left on read before. Please advise.