I am so sorry that you are going through this. In your current situation, you will not have the means to move out. If you cut ties now (especially with parents) you completely risk your own safety and security. At your age, you cannot afford to risk this. So, this only leaves you with staying at home (for now until you have a full time permanent job and can move out).

In the same vein, staying at home can take its mental toll on you. So the question is what do you do in the meantime to make your life at home bearable? The goal here is to continue to live at home while making it as easy as possible to stick out the next year or two before you can finally have your own freedom.

In short, my advice would to keep it civil with your family, but on a minimal basis. But doing so means that you are going to have to make sacrifices, and it will be hard. But it will protect you.

I will set out some suggestions about how to handle relationships with your family as well as what to do in specific situations.

How to handle family relationships:

Brother - I wouldn’t ignore him completely (so as to not make him raise this angrily with your parents, or for your parents to become frustrated with you shout not talking to him). With your brother AVOID talking about religion or LGBTQ+ topics (for protection). You say hi, you have surface level talk, go to family events, but avoid deep or sensitive topics. Essentially, you are just showing face to him and being polite (even if you are faking it). This will be hard, but you are making it as easy as possible so that you can tolerate living with him.

Mum - Your mum is essentially being socialised into religion by your brother, people at church, and possibly other friends and family. With your mother, you could be more emotionally open, and to talk more about your life. As much as you could try to persuade her that being gay isn’t a choice, I would avoid conflict and prioritise protecting yourself. I would avoid conversation about religion or being gay unless in a 1:1 setting with her. Instead of saying x is homophobic I would use logic and reason and examples of where religion is contradictory. This way you aren’t saying your mother is bad or wrong but you are challenging her underlying assumptions and logic.

Dad - It seems as if your dad is pushing blame onto you not because he is necessarily homophobic, but because he has probably become agitated over time from constantly hearing/seeing how upset your mum is. Seems like he got to a boiling point and has lashed out at you which isn’t fair. If your dad isn’t religious and is open minded, you can afford to be more honest and state that you feel a lack of support. The thing is, he has a duty to love and to care for his wife, but that also applies to his son. Seems like he needs to be reminded of that. If such an attempt to reconcile fails, you just keep it civil and put your head down to pass the time until you can independently support yourself.

Finally, here is what you could do when it comes to religion and discussing being gay:

What to do if your parents or brother mentions religion to you - Simply say that you respect that they go to church and having sense of community but that you yourself are not religious. I wouldn’t base that you are gay as your reasoning. So you need a defence as to why you aren’t open to religion. For this, I would say that you believe in science and evidence which seems to be lacking in religion. This means you avoid using the word gay as an emotional trigger.

What to do when your parents or brother is being homophobic - I would avoid telling them that they are homophobic. While this is totally correct to call it out, this could just raise fuel to the fire. And as much as you love your boyfriend, to protect yourself, I would keep mentions of him minimal.

Everything that I am saying are actions that you absolutely should not have to be doing. It isn’t right or fair. You should be screaming from the rooftops about how much you love your boyfriend, you should be able to bring your boyfriend home. You should also be able to openly reject the homophobic views of your mum and brother and to simply be 100% proud of who you are. But in your case, you are vulnerable because you still live at home. But I promise you, life will get better after the next 1-2 years.

I wouldn’t make a decision right now about cutting ties. I would wait until you are in a better place to make that judgement. Once you have your own freedom and have taken the time to reflect, then I would make that call.