Does a loving God send people to Hell?

The other day, I was listening in on a conversation with several church members. They were discussing the instances in the Old Testament of God judging and killing people in large numbers. One of the people involved in the conversation stated that they did not believe that God would destroy a large group of people and send them to Hell due to Him being an all-loving God. That caused me to ask this person what about Sodom and Gomorrah. God completely destroyed those cities and all those who were in them. Did God destroy the cities and kill the inhabitants for their wickedness, only to have compassion on them and allow them to live in Heaven afterwards. What about in II Kings 19:35 where the Angel of the Lord enters the Assyrian camp and kills 185,000 of Sennacherib’s soldiers. Did God have compassion on these people because so many of them died, and allowed them into heaven? We can take it further and look at Genesis 6, where God is sorry that He made mankind because of their wickedness. God chose to destroy mankind with a worldwide flood and only spare Noah and his family. Did God turn around and choose to allow those who were killed and let them into heaven because He killed so many at one time. We can look throughout the O.T. and see where God has allowed the death of large groups of people for various reasons. When one looks at this, they often ask, “Is this the work of a loving and gracious God?” and “Can God be a loving God and kill people and let them go to Hell?” How do we reconcile the fact that God allowed people in the O.T. to be judged and killed in mass groups, and still be a loving God? How do we as believers explain this to a non-believer?