You need to call your isp and request a static ip. Most probably they’ll say its extra but usually around $5. If they say they don’t give static ips to individuals you can request an ipv4 dynamic address and use a ddns. ipv6 only networks also result similarly to double nat
When you’re marrying someone you’re usually not like “lets try this and see where it goes” (that’s called dating), you’re more like “till death do us part” so yes, divorce is failure more often than not. Ending a relationship, not so much