Ending it all when I return home

I apologise in advance for the incredibly long text , but I felt it fit to explain my reasons behind my choice . My life has been an utter misery for as long as I can remember. I have finally decided I will end things once I return back to my home. I tried unsuccessfully two years ago when I was in a much better position, but comically my life has become significantly worse . I’ve been physically sick for many years , I’m always on the verge of fainting / vomiting , walking feels incredibly unstable , it’s just utter torture and has only grown more life limiting to the point where I spend most days inside . I’ve not been able to pursue a further education since being forced to leave school at 15 due to my declining physical health , therefore I can’t get a job . I have few friends, and the friendships I have are extremely difficult to maintain due to my health , my relationship and by virtue of the fact I simply can’t relate to an ordinary person . On the subject of relationships, I’ve been in a relationship with man 17 years older than me for about two years , it began when my health was a little less limiting , in fact I’m staying with him in a different country at present , he was my first love , I love him very much truly , however , having spent more time with him , more things have been revealed which has completely shattered my heart (as dramatic as that sounds) . He hid a wife who was pregnant when I first met him at 20 years old , I later learned he also has a daughter with her , I found out he also has an ex wife with whom he shares two children with , the children he shares with his wife don’t know of the children with he shares with the ex wife and vice versa . However the wife knows of his first family because he cheated on his ex wife with her. Since finding this out , I’ve become a further broken person , I’ve stayed with him however because he’s the only source of income I have and I do feel real love for him . He’s also on interpols blue notice and effectively a fugitive which adds another layer of stress. He tells very often me no one will care / want me because my health has become entirely all consuming and ruined every aspect of my life and I mostly stay inside . In fact , I can’t easily return home because my health has declined so much and I doubt I’d be fit to go on a plane , I can barely walk to the kitchen without feeling I need to faint , however when I do return home I will undoubtedly find a way to permanently end things , different to my previous unsuccessful methods . Besides this , my sister is a drug user and incessantly ignores me save for the part when she needs money , my relationship with her is virtually non existent. My relationship with my mother is tarnished too because I’m a burden and haven’t achieved anything , she also only contacts me for money, she also never defended or tried to protect me which I still hold some resentment for . My childhood was honestly pretty shit too , I suffered great abuse at the hands of my stepfather beginning from the ages of 7 until 15 . I haven’t recovered from this , this was initially the motive behind my first attempt. My father is the only person who never gave up on me , but he doesn’t have much longer left due to his health issues too , I’d give it about 2-5 years if he’s lucky . I know this will utterly ruin my father initially, but I have absolutely no choice , physically and mentally everyday is torment and there’s absolutely no chance of a meaningful future , I want nothing more than to return home and find peace .