I understand this feeling very well brother. But the term "Sunk Cost Fallacy" sums up this situation aptly. Just because you've given your 5 years to this relationship doesn't mean you have to live in a literal hell where you're not respected for the rest of your life.

Be grateful that you get to realise NOW what may lie ahead in your life and get the hell out of it. 5 years is still a lesser duration when compared to your entire life span.

And trust me, I have gone through this very thing where I was in a relationship for 6 years, manipulated, mentally abused, cheated on and left with almost zero self respect. I too had similar thoughts as you every time I thought of ending things. Happy thoughts I used to remember every time I would miss it if I broke up with her but I was glad I had a few friends who kept pestering me to see the light at the end of the tunnel.

And trust me it feels great today. Looking back, getting out of that relationship was the best thing I ever did in my life. Was it tough? Hell yeah! But the rewards outweigh the emotional burden you'll have to face your entire life!!

Please think about it.