Please advise, stay or go away?

I am a person who likes to be stable, not like advanture, if I have a choice.

I have worked in one place for over 5 years, my contract has been renewed with promotion twice. The workplace is a family business. I am the only foreigner.

I am happy with what I am doing, but I work over-time a lot without payment and appreciation, and am disturbed at times by non-professional issues such as no respect, occasional unfairness.

My kid will go to college in 2 years, I feel I need to focus on her, so I need a stable job, that is, I should stay at current job. If I stay, I probably will not have anymore promotion. I already had much more than what the guy (before me) got.

I can find another place, or start my own. If I work part-time outside, I might earn same even more than now as full-time. However, the economics scares me a lot, I am not sure if I can have stable income; I am even more scared if I start my own: time-consuming, a lot headache, unknown income, no time for my kid.

I am in my 40s, I need to have something that can last long. I have a coworker, who is in 60s and has been there for more than 10 years. I feel bad about that situation.

What is your advice, please? I greatly appreciate it.