I have a co worker who is a Christian but we differ on our position on the church. I believe the church has a distinct role and purpose that is different from Israel. She believes we are grafted into being a part of Israel. She believes grace has always abounded and does not believe we are in the age of grace as the church. She also doesn’t believe in any difference in the church vs Israel since we are all one under God. She also observes all the Jewish holidays and believes they point to Christ as Messiah and these are the only holidays we are to keep. Is this the correct way?
It sounds like your friend is from a Jewish background. It’s not unusual for a Messianic Jewish believer to identify more with Israel than with the Church. After all the Church has been responsible for more persecution of the Jewish people than any other group. Many Messianic believers are reluctant to associate themselves too closely with the Church, fearing it would be seen as a betrayal by their people.
In your place I would leave the topic of Israel and the Church alone and focus more on making sure she truly believes that Jesus died for all her sins and rose again to show that His death was sufficient. All the rest can be worked out after the rapture.