I am not an expert or scholar, so please do not take everything I say to be an absolute truth
. I advise you to see a good imam who can explain things to you and direct you about what you can do to help yourself through islamic teachings.
Here are the symptoms of the "love magic" that I found on one of the muslim websites that discusses kinds of magic that may struck a person.
Symptoms of love sihr:
1. Excessive feeling of being in love (being obsessed about a person)
2. Excessive desire for sexual intercourse with the person
3. Inability to bear the person not being in your presence/excessive yearning for their presence
4. Great desire to actually see the person in question
5. Unquestionable following of the person (doing whatever they ask you to do even if it hurts you)
The purpose of this kind of magic, according to this website, is for two reasons: 1) to cast the magic on the person desired to be with and 2) to make a spouse 'love' you more.
So, love magic is not intended usually to destroy one's life.
You mentioned that you "see the jinn" of this person. It sounds like that your excessive infatuation with this person is causing you to visually, and perhaps auditorily, hallucinate. A hallucination is something anyone can experience in life and may be induced by stress. Also, a hallucination is a symtpom of a mental health problem. There are different kind of hallucinations. Some are visual, auditory (hearing), olfactory (smell) or tactile (physical sense of a touch). Some people experience some or all.
Now, sister, I do not know you personally. I do not know what you are going through. But I advise you to first continue to pray and focuse on Allah swt only. Second, go see an imam and talk to him. Tell him all that you experience and feel. He should be able to direct you what to do. And third (you may not like this one), please also see a therapist/psychologist or psychiatrist. Your problem may be something else.
Keep in mind, that evil jinn can attack person spiritually without any help from a person casting spells. Also, how is it that you came to a conclusion that this guy is using black magic? You must seriously revisit all that you are able to recall, because as you know Islam teaches that being suspicious of someone may cause you to sin by accusing the person falsely.
Just because this guy was new and no one was socializing with him at first, does not mean he is a black magic performer. It could simply mean that he was new and people did not know him all that well. Perhaps you fell in love with him and for some reason, your other problems in life, the stress of having feelings for someone who does not care as much and other factors, may have caused you to experience a mental break down in some way.
Mental health problems are the same as physical problems. Nothing to be ashamed of. There are thousands of people who struggle with mental health problems. I work in mental health field and it breaks my heart to see how much one can be tortured mentally.
Do not allow yourself to get to the point where your mental health deteriorates so badly to the point where you are unable to distinguish what is real and what is unreal. Please. I do not want to sound mean. No. I want to help you. Regardless if your problems are sihr caused or not, they impact your health (physical and mental). And you need to deal with it.