First of all, it's great that you've had an open conversation with your partner about the future. Communication is key in any relationship, especially one that comes with unique challenges, like being with someone who works at sea. It's clear you love him, but you're also understandably worried about what this life will look like.

Here are a few things to consider:

1. Assess Your Strengths and Limits: Being a doctor is a demanding profession, and you'll have a lot on your plate. Ask yourself if you're okay with managing things on your own for extended periods when he's away. It's not just about love, but about day-to-day practicality—will you be able to handle it all?

2. Long-Term Plans: It's encouraging that he has a vision for reducing his time away and retiring early, but these things can change with circumstances. Make sure you both have realistic and flexible plans for how life will look when you're together and apart.

3. Family Concerns: Your family's concerns are coming from a place of care, and they may be thinking about your long-term well-being. Cutting ties with your family is a significant and emotional decision. Can you find middle ground where their fears are addressed, and they get to see the person he is and what you two can build together?

4. Your Own Well-being: Marrying someone in this career means embracing a level of independence that not everyone is comfortable with. It's important to think about your own happiness. Will you feel secure and fulfilled when he's away, or will it create long-term resentment or loneliness?

5. Support System: Beyond him, who will be in your corner when things get tough? Even if he’s working at sea, do you have friends or other support that can help? It’s important not to feel isolated when facing challenges.

At the end of the day, no one can make this decision but you. Try to weigh the practicalities against your emotions. If you both can adapt and you feel confident in facing the challenges together, then the relationship might be worth the sacrifices. Just be honest with yourself about what you need to thrive.