I confess that I've been inviting sinful thoughts of sexual nature. I don't understand why taboo things only make it more appealing.. I've been really good at controlling many urges and I am just tired of feeling bad about it, because I know that I have good character and I always try to be kind to others.. but there's this sense of guilt lingering at the end of each day, and sometimes I feel like justifying it in my head by weighing it against my other actions.. so it's just that.
There are a whole lot of people that struggle with the same thing as you do so please know that you are not alone in this. It can be very hard to control your thoughts every minute of the day. I believe it would be an exercise in futility.
These may indeed be sinful thoughts but perhaps only that, and in that regard you may not be committing sin. Of course, it is best not to dwell on these thoughts or you may be tempted to act on them. It is at that point that sin would be committed.
Being kind to others is a very good character trait to have.
You don't have to justify anything at the end of the day but pray for God for you not to be led into temptation. That's part of the Lord's prayer. I make it a point to pray this prayer each day. I highly recommend it as part of one's daily routine.
No one is perfect and each one is flawed to one degree or another. Myself included.
Take care and God bless you.