What to do?

[BL42]

Should I tell her these things? Write it in a letter and give her?

No! Don't say...DO! Remember, Actions > Words.

I told her two nights ago after I had a really hard day dealing with her being at work with him, that it's time she starts giving me a reason to keep trying. I also said that if her job is more in important than me then that tells me all I need to know and at some point, it has to be addressed. A lot of times when we have had hard conversations, she asks me if I want her to leave. I take that as her hoping I say yes because she doesn't have the nerve to do it again. I finally told her to stop asking, if I ever reach that point she will be the first to know.

Typically in DB'ing the standard response is no R talks. Don't pressure or debate, just listen an validate. Not sure in your case what most would recommend considering your W moved back, says she wants to work on it, and is going on date nights and having sex with you. Maybe some R discussion is warranted. However, in general you should minimize the pressure, guilt, and arguing and instead do more listening and validation...in combination with working on yourself to fix your issues and up your attraction.