I sure understand how you're feelling. We did 20 yrs. in the Navy & 10 yrs. were done during the Viet Nam war. Out of that 10 yrs. he was gone a total of 7 yrs. Our carrier was the first involved when that war broke out.
Our ship was gone 10-11 months at a time. That's a whole lifetime for sm. kids. Trust me, it will all come to an end though it sure doesn't feel like it.
Just try to stay busy.