Do I come clean or make up an excuse?
我需要坦白真相还是编个借口？
Should I come clean to my girlfriend/wife about my past relationship?
我需要向我得女朋友/妻子坦白我过去的情史吗？
Should I come clean or just let it go after lying about not having a past relationship?
我应该坦白还是撒谎说我过去没有感情经历来掩盖？

I think you should come clean about where you were last night.
你昨晚在哪我觉得你应该说实话。
I think it is time to come clean with everybody about our financial issues.
我觉得是时候向大家坦白我们现在的财务问题了。