I would like to get a neutral opinion on my girlfriend's behavior and whether I should just accept it or am actually right being not ok with it. I have to admit I'm not particularly good at relationships; I also realize I am quite attached to my girlfriend. So I am not sure and don't want to be overreacting.

I'm in a long-distance relationship with that girl in our fifth year now. We met when I was working abroad. We see each other 2-4 times for some weeks each year; the rest of the time we communicate every day (a few texts in the morning and during the day, then a call when she goes to sleep).

Every once in a while she kinda disappears, not texting/calling me, not picking up my texts/calls either. She will eventually come back after a day or a few days, apologizing for it and telling me she had family issues again and that that's how she coped with it. It's just happening again; no response to my text since yesterday afternoon, not the usual good-night call, not the usual good-morning text this morning, no picking up my calls since then, and I don't know what's going on.

I'm not sure if my expectations are completely over the top; maybe I am just insecure and too attached. But I actually feel it's reasonable to expect from a healthy relationshop some sort of regular communication, and even more so from a long-distance relationship (and even more so when you have a history of trust issues, see below). After all, I am not talking about 24/7 availability here, but just a few touch points during the day to make the other one feel everything is okay and, well, be a couple.

Since I rationally cannot understand how someone wouldn't be able to react/respond for 24 hours or more in today's world, these acts of disappearing leave me anxious and are emotionally disturbing for me. They trigger a stressful mix of trust issues, fear and worries, but also anger, disappointment, and feeling helpless to be stuck in a relationship that is not healthy and not improving.

I have to add for context that a year or so into our relationship I found out that she went on a date with someone behind my back. Though it was only a date, no physical action (at least so she told me), it destroyed trust and made me a jealous and mistrusting partner. My jealousy actually led to her first disappearing which was quite extreme as she didn't come back for two weeks and only did so after I was able to reach her friend and tell her that I was on my way travelling there to see if she's ok.
Her reasons obviously were made up (even when you are at a hospital, as long as you are not in coma or intensive care, you can easily let someone know about your situation), so I believe she actually was on her way out leaving me, and only did stop because of me going there. Even though our relationship improved since then, everytime she disappears now it's triggering again those feelings of fear that she might be cheating and/or running away from me again, together with general worries that some kind of accident might have happened.

Maybe the worst of all, however, is that I am feeling quite helpless and depressed. Since we talked about this quite often, including me explaining how her behavior makes me feel and what my expectations are, I feel like a betrayed, disrespected fool who can be pushed around because he will always come back and give in. That's why I normally react with taking time off myself because I just don't know what to do. I am too weak to break up, and too disappointed and confused to just forgive and turn to normal (which is what she wants, to say sorry and that's it, without actually working on it). To be clear, I would totally be willing to forgive and move on. I just wish she would show me that she actually cares by being the one who's coming back and coming back with a solution or at least with a bit of understanding and a constructive, serious conversation. In the end, however, I am the one who's calling her again to fix everything by just accepting it. And so I am getting even more insecure and attached, by feeling our love might not be equal and I am the weak one.

Am I overreacting? Are my expectations too high; is it actually okay that your significant other might disappear and ignore you to cope with problems? Should I be more understanding and accepting?