Ever since I've been in ministry I've been in thankless positions. Sure, ever so often there are encouragers and sweet old ladies that love on you, but it seems like the people you really invest in are the quickest ones to not show appreciation.
And you know what? That's perfectly okay. Jesus doesn't call us to follow Him for the accolades and pats on the back. He calls us to deny ourselves. Denying ourselves can be very taxing on our human nature.
During a long deployment, it's especially hard. It's even harder when you're the Chaplain. I'm the one who is supposed to listen, encourage, take care of, and thank others. It's great! I love doing that.
At the same time, when you get little to nothing in return, it's difficult. It will wear on you. The enemy will use it to frustrate.
Again, I'm not saying that you must receive something in return for your spiritual investments. However, it is nice to know if they're paying off every once in a while. This is where prayer and complete reliance upon God come in. God is sufficient and we have to be reminded of that!
I encourage all of God's people to take extra measures to encourage people. Take extra measures to take care of one another. Show your pastors appreciation, and let them know when they've made an impact on you!