Good for you Diana.
I've been thinking about you, hoping you would find the courage to act. Life is too short for pointless misery. The choice was an important one not just for now, but for the lessons it will teach you about how to live the rest of your life.
Fear of being alone, missing a loved one - these are hard things to face up to but doing so will enable you to find happiness again. Once you start letting fear dictate your actions it's a hard habit to break. It's also almost always futile, people get hurt anyway despite (and often because of) their attempts to protect themselves. Far better to learn to trust your instincts, take the risks and go for what you want despite the fears.
He loves you and you still care for him. Be kind but be clear and firm. I wouldn't go into the whys other than to say that despite the love, neither of you has been happy and both of you deserve more.