People Make Time for What Matters
People always know how to make room for those who matter to them. They will find ways to adjust their lifestyle to accommodate you. They will find time to dedicate to you. They will always figure out a solution to every problem just to be with you. There are no exceptions to this rule.
Your texts do not go unanswered every time if you matter to someone. Your calls will be picked up. You will receive warmth from the other end every single time. This is the normal behaviour of someone who cares about you. All the love stories you hear, where the boy goes to extraordinary lengths to meet his girl, are a sign that she holds significant importance to him.
Isolated incidents aside, if you are routinely sidestepped, your messages do not get answered on time, you are consistently put on low priority, and they have time to post stories on social media while your message remains unanswered, the simple answer is that you do not matter to them as much as you thought you did. Like I said, there are literally no exceptions, apart from isolated incidents where someone is genuinely not in a condition to answer. But those are not repeating patterns. They are isolated for a reason.
The worst thing you can do in such a case is pick a fight with them over being ignored. Their behaviour is a message; what more do you want from them? What do you expect them to say to your accusations? They are not going to confess and be embarrassed about their own conduct. So, naturally, they will give you excuses.
The only approach is to give them the distance they seem to want. Drop a note and wait for them to respond. If it becomes too much, ask them if you are still a priority. It is okay if you are not. Because no matter how much it hurts you inside, the fact of the matter is that if you do not matter to them, nothing you say or argue will make you important to them.
Maintain your distance and hope they realise that they have not been focusing on this particular relationship. If the pattern continues, you have to lower your investment in that friendship or relationship. It is alright to be hurt; it is not alright to keep begging to be prioritised.
You do not have to hate them. Understand that this is a cycle of life, and sometimes, it is simply time to move on.