I am not ready for a long-term relationship

I've been dating my partner for over a year and half and I'm starting to realize that I'm not fit nor ready to be in a relationship.

I feel that I was emotionally absent starting from a few months ago and that I couldn't bear the baggage that comes with being in a relationship. For example, after having an emotional conversation with each other, I often feel mentally drained. Along with the fact that both of us have been struggling with our mental health, I don't think I am fit to be able to help my partner.

My parents are both religious and conservative. Unfortunately for them, my partner is apart of the LGBTQ+ community. Because of this, I've been having a hard time thinking about how my parents would treat and perceive them if I were to introduce them. Since I am still dependent on my parents, I don't think I will be able to prioritize my partner over them.

Despite still having feelings for them, I have been recently thinking that I should break up with them. I feel that if I were to continue this relationship, I would just hurt them even more. I am unable to give them the help they should get and to fulfill my part as a good partner.

However, I'm also scared of what will happen to them once we are to separate from each other considering the state of their mental health. Also, since we are becoming long distance, I don't want them to think it's their fault for moving away.

What should I do? I know I should tell them in person and not over text and to be frank about it, but I'm scared of how they'd react.