Wow girl
how amazing you are having this conversation at 18! I am so in awe of you and I am happy for you to be this self aware.
I love being alone. One time, my therapist tried to convince me I probably had abandonment issues and I was like maybe but most likely it was my fantasy to be abandoned so I am not intruded upon or handled. Abandonment moments were like relief moments for me.
My point is this, I love it so much it was probably one of the most deep and satisfying conversation I had with my husband after we moved in (after 6 months of long distance dating). I said straight out, hi babe, I love being with you but I also really love being alone and for now I do not want to give up. He also loves being with people (way more than me).
But I think because I framed in a way that also announces my love and commitment to him, he was OK with it and eventually he started to find being alone (which he avoided in the past) quite creative and relaxing after a long day at work.
My advise to you is this: a relationship is not for just avoiding alone time - so that could be a belief you have. A healthy relationship does not intrude or take time away from self. So just be honest, vulnerable, and state your needs to your b/f. If he balks or tries to make you feel like a freak, then perhaps he is not the one for you. but I think most reasonable people will understand the need for self time.
You will have to be considerate about how you bring it up. It is not that you are taking time or energy from the relationship, it is that you are enriching yourself to be a better partner.
Hope my comments help you.
