Hey @gamer2000,
Like @Dashinka said, you can just show the interviewing officer how you communicate with each other. I know individuals who used a messaging app that translated English to Chinese, and Chinese to English, as soon as they sent their messages to one another; they didn't have any issues with USCIS or the interviewing officer. As with all things, you just need to ostensibly show that you have a genuine relationship (with photographs, many texts to one another, calls, etc.).
In regards to your passport question, I think you are referring to the Custom and Border Patrol website here. CBP does keep track of every non-U.S. citizen that comes in (and out of) the country. Your wife, if she has visited the United States, has this record (it's called the I-94 record). I don't believe they keep track of U.S. citizens or permanent residents, since they can travel freely in and out of the country. Therefore, you most likely don't have one. However, you will likely receive a stamp once you enter her country. That's good evidence that you travelled to visit her and spend time with her. I would include that in your bona fide evidence, that is, evidence to show that you both have a genuine relationship (once again, photographs, texts, calls, gifts to each other, trips you've taken together, etc.).
If you have already filed your petition through USCIS, you can show your new passport stamps at your interview. They will ask for evidence of your relationship anyway, and this will show that you have continued to talk to her and visit her as your petition was being reviewed/processed.
Hope this makes sense, and best of luck to you both!