Anytime you make the decision to put God first and develop your relationship with Him you have a fight on your hands. Don't give up, don't be discouraged, stand your ground. Recognize that ultimately your fight is not with flesh and blood (young ladies) but with demonic forces wanting you to be unsuccessful at meeting your goals and ultimately destroy your God ordained destiny. The Apostle Paul - one of the most successful single men that ever walked the face of the earth gave the spiritual solution to your dilemma in Ephesians 6: 10-18 (The Living Bible):
10. Last of all I want to remind you that your strength must come from the Lord's mighty power within you.
11. Put on all of God's armor so that you will be able to stand safe against all strategies and tricks of Satan.
12. For we are not fighting against people made of flesh and blood, but against persons without bodies--the evil rulers of the unseen world, those mighty satanic beings and great evil princes of darkness who rule this world; and against huge numbers of wicked spirits in the spirit world.
13. So use every piece of God's armor to resist the enemy whenever he attacks, and when it is all over, you will still be standing up.
14. But to do this, you will need the strong belt of truth and the breastplate of God's approval.
15. Wear shoes that are able to speed you on as you preach the Good News of peace with God.
16. In every battle you will need faith as your shield to stop the fiery arrows aimed at you by Satan.
17. And you will need the helmet of salvation and the sword of the Spirit--which is the Word of God.
18. Pray all the time. Ask God for anything in line with the Holy Spirit's wishes. Plead with him, reminding him of your needs, and keep praying earnestly for all Christians everywhere.
In other words, you must be devoted to the Word of God and prayer if you are going to be victorious in your situation. You must read and study God's Word daily and you must pray daily. When you do this God will give you wisdom and strength to handle the potentially compromising situations you may find yourself in and in some cases may remove wrong people out of your path and navigate you away from difficult situations.
Practically speaking, I recommend the following. If a young lady indicates she is interested in pursuing a relationship with you beyond a friendship - kindly but firmly tell her that at this point in time in your life you are not interested in romantic relationships. If she gets offended, let that be her problem and move on.
Let the words of your mouth and the actions of your body agree. In other words, don't say you don't want a girlfriend, but then always socialize with the girls in the church. Women who want to be married will misread you. Socialize in a group setting with the other people in your church where men and women are present. Don't engage in flirtatious behavior that will lead ladies on such as smiling at them, winking your eye at them, staring at them. These small gestures say to many ladies - I think he likes me.
Changing churches is a major move. Being at the right church is crucial for your success in the Kingdom. If the situation is unbearable after you have done your part, pray and seek God's guidance as to whether He may be directing you to a church where the women are not as aggressive and needy because they have been taught how to wait on God and also talk it over with your Pastor before making such a move.
God will be faithful to give you the victory if you will be faithful to pay the price!