Only you can answer that question, of course. Perhaps you still have hope that your husband will change; perhaps you fear being alone even more than you fear being hurt yet again. Down inside, you may even feel that you aren't worthy of having a happy marriage (although that isn't true).
But whatever the reason, the most important thing I can say is that God doesn't want your marriage to be this way. God gave marriage to us, and He meant for it to be a source of joy, not heartache. The Bible says, "He who finds a wife finds what is good and receives favor from the Lord" (Proverbs 18:22).
This is why I urge you to commit your marriage—and your whole life—to Jesus Christ and ask Him to help you rebuild your marriage. God loves you, and He is even more concerned about your marriage than you are. Yes, your husband is responsible for breaking his marriage vows; what he has done is absolutely wrong in God's eyes. But have you done everything you possibly could to make your marriage happy and fulfilling?
Perhaps the place to begin is with your words. Words of love and encouragement can do much to bring healing; no one likes a home that is constantly upset by bickering and arguing. The Bible says, "Words from a wise man's (or woman's) mouth are gracious" (Ecclesiastes 10:12). May God bless and encourage you.