No, you don't lose God by making sins, but if you think God rejects you you will feel lost.

When one has sinned the sin becomes a wall between him and God. It is very important then to talk to God about it, ask for forgiveness and a way to make things better, knowing he listens through any wall. I think people can forget about God if they sin and think the sin is unforgivable. But who are they to judge? How you handle sin is a test on how much you love God and believe in His love. Also how you respond to other people who sin by hurting you. Do you forgive? If you don't you may not think God will forgive your sins either, because people have a tendency to project their own concepts on others. Even on God who is more loving than we can ever fathom.