I believe that you have to seek God to be filled with the Holy Spirit. Have you noticed in Ephesians 5:18, it says "be filled with the Spirit?" It means continuously. Then, it goes on to say, "husbands love your wives, wives submit to your husbands." That is the result of being filled with the Spirit, 3-4 verses later if you read Ephesians 5:18.
The fullness of the Spirit is for your family life if you read Ephesians 5:18 all the way to chapter 6, verse 4. It's entirely relating to family life and then to fighting the devil in chapter 6 verse 10 onwards. That's the only place in the Bible where being filled with the Spirit is mentioned.
So, the primary purpose of being filled with the Spirit is to live a godly family life and to stand against the devil and overcome him. We need to seek God to be genuinely filled with the Holy Spirit, and you'll know you're filled when you're able to overcome.