Repent over the sins you are ashamed of. Learn to understand what you should and should not be ashamed of. That is a matter of discernment. You may have an acute sense of natural justice that may help here. Or turn to the scriptures for help and guidance. But still the rule applies. Repent of the sins you are ashamed of. These you must repent of the rest you need not.
Luke 15: 8-108 “Or suppose a woman has ten silver coins and loses one. Doesn’t she light a lamp, sweep the house and search carefully until she finds it? 9 And when she finds it, she calls her friends and neighbors together and says, ‘Rejoice with me; I have found my lost coin.’ 10 In the same way, I tell you, there is rejoicing in the presence of the angels of God over one sinner who repents.”
And if you are unsure whether you feel ashamed or not, then there is nothing you need repent. Simple, wouldn't you say?