Marriage with Longtime Girlfriend
My girlfriend (F19) and I (M20) have been together for 5 years, with the last 2.5 years being together in college. We are more than ready for marriage, and are in a decent enough financial situation to have a wedding that we want as well as possibly even buy our own home afterwards. We are both Christian, her Missouri Synod Lutheran and I Catholic, but we both have made concessions and I will most likely convert in the future before we have any children. We nearly fully agree on every political and moral issue, we agree on how many kids we want, we have both abstained until marriage, and we are fully in love with each other.
My family absolutely loves her and she loves them. Her family all loves me for the most part and invites me on vacations and regular day trips. Additionally, our summer homes are 3.5 hours from each other so our families have never met, and our college is much closer to my house, so her family knows me well, but not as well as mine knows her.
However, her father is still weirdly against our relationship and has portrayed his doubts to her about me multiple times. He has also told her on multiple occasions that he quote, "failed in raising her." In addition, I am allowed to stay at her house any time and go on trips with them, but she can never stay at my house or go on trips with my family. All of this inconsistency between his beliefs has really upset my girlfriend to the point where she finds it hard to even talk to him anymore. Her mom is much more understanding but doesn't ever seem to back her up in conversations or decisions about things.
Unfortunately, I have no idea what to do about this, as he never talks to me and barely acknowledges me. We are more than ready for marriage, but her father's inability to trust and support his daughter in this is making it exceptionally difficult.
Does anyone have any advice?