Should I give up equity and brand owner tag for high paying job?

Hi I have dedicated 3 years of my life working day night to build a brand in ecommerce segment, from product sourcing to selling, finance reconciliation and cashflow management. I am getting 10% of profits after all expenses plus have 3% equity [to be offered soon]. But my pay is not more than 1 lakh per month and I don't think I will be able sell equity anytime soon because my partner is a very rigid guy and nobody seems interested in investing in us. For past 1.5 years he has become sluggish as we are earning 6-7 lakhs and has drinking problems, all the major task are done by me and i dont have support to hire right kind of people as we are bootstarpped and everything is expected from me. I can take leave whenever i want but i am expected to work on sat sun too.

Now i have been offered 1.5 lakh per month plus incentive for similar role in an new brand as Brand Head of established and funded ecommerce company. They have funds for growth and a team for expansion. Company COO belives in me and is offering this role, he knows his current team is foolish, lacks enthusiasm and slow to execute. Sat-sun off Problems

1. 3.5Lakh is pending to be paid to me from current firm. How should i approach to get that money?
2. How to convince my partner who is an industry veteran and my mentor that i want to leave?
3. Anything I should be confirm from latter company before quiting in previous firm.

What should i do?