You’re not entitled to a date or relationship with that certain someone. Even though you might be The Nicest Person on Earth TM or you bent over backwards to accommodate them by busting your boundaries, they’re still allowed to say no. They don’t have to reciprocate your interest, and they’re allowed to not want a relationship. They’re allowed to choose someone else, and you’re also allowed to feel wounded about it. That makes total sense.
You’re a human with feelings and rejection hits hard, especially when it pokes at emotional baggage. Still, that doesn’t entitle you to a relationship or their attention. The fact that they did what they did doesn’t entitle you to trash them.
Even though you apologised after doing something unintentional, questionable or downright shitty and shady, you’re not entitled to forgiveness. You don’t get to say that it’s ‘over’ because you apologised. And even though the person may have forgiven you, you’re not entitled to be let back into their life to the same degree as before. You’re not entitled to their trust, and you’re certainly not entitled to them erasing their memory.
They’re allowed to say no even though it doesn’t suit you.
You don’t get to say what is or isn’t OK or to make your intentions more important than their impact. They’re allowed to define their boundaries and who they interact with.
If they cut you off or step back, you’re not entitled to wage a campaign of harassment against them. That doesn’t mean that their distance isn’t hard to swallow, but you’re not entitled to destroy them. You can’t decide that you’ll talk to the press at thirty-day intervals until they pay your attention-ransom demands. It’s overkill to pair up with other similarly-minded folks and to weaponise your woundedness. You don’t get to spread rumours about them or destroy their life because they dared to move on with someone else or be happy without you in their life. You don’t own them. Incidentally, you’re not exactly making a strong case for repairing and restoring the relationship or for being perceived the way you want to by behaving in this way.