I actually don’t think this is cringey at all - I think this is an important life skill.
Sooner or later, everyone has to deal with someone who comes on way too strong, doesn’t take hints, and generally makes it clear that they’re way more interested in you than you are in them. This can happen with friends, coworkers, romantic prospects, neighbours - pretty much anyone in your life. Sometimes, you can manage the situation by keeping the person at arm’s length and giving gentle reminders about boundaries whenever they start to push it. But sometimes, people push and push and push no matter how firm you are and how many reminders you give - and sometimes, this person’s refusal to back down can start to negatively affect your mental health or other relationships in your life.
The first thing you need to remember is that someone else’s refusal to take a hint is not your fault. Having someone disrupt a big event like a graduation to ask why you aren’t taking their calls is definitely embarrassing, but you aren’t the one who should feel embarrassed by that - they are the ones who crossed a line by confronting you in public to try to bully you into answering their calls, and they are the one who should feel embarrassed about that happening.
For what it’s worth, I have also been in this situation before, several times in my life. In high school, one of my classmates decided that we were “best friends”, even though I had no real interest in being more than just high school acquaintances. She religiously tracked when I was online to see if I was “ignoring her” (I was), she called my house so much that my parents got annoyed, and she had a tendency to show up at my house unannounced to “hang out”, even at 7am on a Saturday. In grad school, I matched with someone on a dating app who quickly became obsessed with me and couldn’t take a hint that I wasn’t interested - he created multiple social media accounts to harass me and sent messages saying he was going to show up at my campus to try to find me. Those were deeply unpleasant experiences for me; I felt like the “bad guy” for not returning their affection, and trying to explain to other people that “someone is completely obsessed with me” made me feel kind of self-centered, even though it was objectively true. It sucks.
I know that saying “no” to someone over and over again feels awful. I hate saying no to people, even at my own detriment - but sometimes, that’s what you need to do. You are not a bad person for putting your foot down when someone else is refusing to listen to you and is intruding on your life. You’ve already done everything that I would recommend you do in this situation - you started out nice, you reminded this person of your boundaries, you politely asked for space, you gave specific instructions for future interactions - and this person is not responding. You have done what you could, and it’s time to take a firmer stance here. You aren’t a bad person for having boundaries and wanting them to be respected - this person has had several chances to correct their behaviour, and they have chosen not to take them. That’s on them.
At this point, I think it’s okay for you to be frank with this person. Tell them straight up that you don’t want any kind of relationship with them and that you would like them to leave you alone. If that’s too direct for you, tell them that their behaviour is rude and that you are starting to feel harassed. I know that it’s hard to be that firm with someone, but sometimes this is what another person needs to hear - they need to be told, straight-up, that you’ve had enough of this and you’re done. Is it possible that the other person will see you as an asshole? Yes, in all likelihood, they probably will. But it’s important that you not take that personally - it is not your fault that this person’s repeated actions ended in predictable consequences for them. You are not a bad person because someone else is upset that they were called on their bad behaviour.
And if the person still isn’t taking the hint, sometimes the only option you have left is to cut them off entirely. Block their number, delete them from social media, and don’t respond to their attempts to get in contact with you. Being able to get in touch with someone is a privilege, not an absolute right, and when someone abuses that privilege, sometimes they lose it entirely. You aren’t ghosting the person - ghosting is when you duck out of someone’s life without even telling them what they’ve done wrong. You’ve told this person what they’re doing wrong, repeatedly, and it’s okay to take away their opportunity to keep doing it.
Having to get stern with an eager person who can’t take a hint is tough. Rejecting people is hard, and most of us hate doing it. But sometimes... you just have to. You aren’t obligated to give someone an 18th or 19th chance to respect your boundaries, and you don’t have to have a relationship with someone just because they really, really, really want you to. You have a right to decide who you want to be close to, and you should never feel bad about having to be frank with someone who is otherwise completely unwilling to respect your wishes.
Best of luck to you,
MM