Guy's Behavior

What do guys think if you ignore their text after they ghosted you?

I have been talking to this guy for awhile. We almost dated in high school (now I'm almost done with my second year of college) but we never did and he ended up moving almost two hours away after our HS graduation. Since then he has gotten in touch with me multiple times over those two years and I haven't always responded (due to not being active on fb messenger), but tired my best. Either way, he never gave up and would always contact me. I finally gave him my cell number and a few times we would talk constantly and really hit it off, but nothing more. This past year we even started talking on the phone and would stay up all night just talking. He would tell me how much he loved our phone calls and that he has never talked to anyone else on the phone for that long in his life. We would talk almost everyday (flirting of course) and basically never stop. If I ended the conversation because I was busy he would text me and hour or two again later because he wanted to talk again lol. Anyways, we went through this phase a lot where we would text each other almost every day and then it would fade (usually because of me being busy) for a few months and then start again. Anyways, this time around he asked me how I was doing one day (after texting constantly for days before) and when I replied he never texted back. He never ever does that so I found it weird, but I didn't text him back because I knew he was ignoring me so I didn't text him again. A few months later he texts me again. I haven't responded because I don't think any good can come of responding to someone who ignores you, but idk? Why did he ignore me for so long and why is he texting me again? Should I text him back? Why would someone text you after ignoring you for so long?
What do guys think if you ignore their text after they ghosted you?
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