DP and I have been together for 4 years, 2 kids - 1 his step daughter, 1 our daughter. We're sickeningly happy - no doubts at all that I want to be with him forever. He's hinted he will propose this year. However, when we met he was seperated from his wife whom he still hasn't divorced. I don't believe we should be engaged til they're divorced, despite them having no contact. AIBU?