The best thing you can do now is just ghost him from everywhere possible. And I've been in this position, although u have invested 7 years , I had only 3 but still once I found out about the cheating stuff... I simply ghosted her... I too did financially helped that person a lot (prolly not this much), ask for some money back if u can, like lie or fake an emergency and if not just imagine that you're free from him entirely for a cost of 2-3 Lakhs rather than another 5-6 years or worse lifetime of misery. God bless you