Medium Distance At Uni

Hey. This is the first time i've ever asked a personal question but i don't want to ask my friends in case they think im a horrible person. i'm in my 2nd year of medical school and i met my boyfriend last year whilst he was also studying at my uni. at the start i was so in love with him and i was so convinced he was the one i will marry as i only date to marry. but once he moved back home after graduating its just been so so difficult and i feel like i'm not the type of person to handle something intense as this at the age of 20. he tries to visit me once a month as much as he can, and he loves me so so much. he does everything he can for me, sends me gifts, heartfelt letters and motivates me so much, asks me about my day and is so invested in my personal growth. in summary, he is an amazing person and someone who deserves the world. i also do the same, and im helping him find a grad job. the horrible thing is, whenever he's at home, i feel so disconnected from him. he feels like a stranger to me rather than my boyfriend, and then when he comes to visit me, it takes me a day or so to get used to him and normalise myself to how it used to be. and then when we are together in person its so nice, we go back to our old selves and are so happy.i think the difficult part is that we went from basically living together and doing everything together at uni to seeing each other now and then, and i just don't feel like i can handle it. i miss last year so much, and im beginning to question whether this is all worth it at such a young age. because he's living at home, his life is just revolved around his part time job and me, and he doesn't stay busy too so we just text each other like every 10 mins and it feels like a chore. he can sense a small change in me and because he can see when im online he will know im airing him, and start overthinking. so i can't even take my time to reply to his constant texts. i genuinely feel like i don't deserve him and have the capacity to shower him with the love he deserves. everyone knows about us as a couple, and are rooting for us to last and get married, including our siblings and it would just shatter me to let everyone down. basically, my boyfriend is someone i would totally marry and settle down with in my late 20's but just not now, i can't handle the pressure of continuing a long distance and long term rs. i sometimes find myself wondering what it would be like if i was single and just allowed to flirt with whoever i wanted to at uni, and focus on my personal growth without worrying about a boyfriend. what on earth do i do