Relationship and visa Advice?

Hey everyone, I’ve been in a relationship with my girlfriend from the USA since 2018. We met while she was studying abroad for the summer, and we’ve been doing the long-distance thing, traveling back and forth every few months. The plan was always for her to move here for her master’s degree.

Covid delayed things a bit, but she moved over in 2022 to pursue her studies. We haven’t lived together yet because her university is in a different city, and I also had a work stint in mainland Europe. Now, we’re planning on getting a place together in the new year.

Here’s where I need advice: Her student visa expires at the end of 2025. With that in mind, I’m wondering if the best path forward for us is to get married? We’ve been in a relationship for over 6 years and want to make sure we have a plan in place for the future, but I’m also open to hearing about other options or experiences that may help us decide.

Looking forward to hearing your thoughts and any advice you might have!