Why are you opposed to it? Why do you think it's a tragedy? Because abortion kills a human being? Because human life is a precious thing and we shouldn't destroy it? OK, good answer. Now about that "but"... how can you seriously say the rest of that sentence?
Let's take other things that you are "personally opposed to" and see if you can add the same "buts" to those sentences.
"I'm personally opposed to rape, but... who am I to tell men what to do with their bodies?"
"I'm personally opposed to child abuse, but... we have to consider the feelings of the parent."
"I'm personally opposed to kidnapping, but... sometimes it's the best choice in a tough situation."
"I'm personally opposed to pedophilia, but... if others believe it's OK, they should have the right to do it."