Sometimes we selectively read the gospels, excluding all of the harsh bits so that we end up believing that to be a good Christian we must be a doormat and allow others to walk all over us.
Yes, the gospel does say we must forgive 7 times 70 times , or 77 times. But forgiving someone and continuing to put up with the behavior are two very different things. In today's gospel, from Mark 12 the owner sends servents three time to retrieve what he is due and each time the tenants behavior only gets worse. He finally sends his beloved son and him they kill as well. Mark 12:9 does not say, "Out of love the owner will continue to forgive them and let them keep behaving the same way over and over". It says he will destroy them and give the vineyard to others.
For a less harsh but equally limiting example we can look at Mt. 18, the instruction on how to deal with those who sin against us.
v. 15 talk to him by yourself
v. 16 take one or two others
v. 17 use the whole church
Then treat them as you would a gentile or tax collector.
We must love others, we must forgive in our heats, but we must also hold one another accountable. If our brother or sister sins against us, it is not God's expectation that we simply suck it up and tacitly condone the behavior. We too, by virtue of our baptism, are the beloved children.
As the master in today's gospel says "They will respect my son." We are to treat others with respect, we are to respect our own bodies and we have a right to be treated with respect by others, particularly our fellow Christians. How did Jesus respond to those who disrespected the temple? He did not say to the money changers, "I'd appreciate it if you would stop, but God loves you, so it's ok if you keep doing what you're doing"
We can and must do both: forgive in our hearts (harbor no anger or animosity) and set boundaries on behavior. We can and must at times even with those closest to us draw a line and say no more.