This discussion on “loathsome” bodies is interesting. Most the replies have been accurate regarding how humans are supposed to love our gifts from God (including our lives and bodies). However, I find it interesting that nobody has provided a reason for loving our bodies with a source (although someone did vaguely reference St. Iraneus’ teachings).
OK, you asked.

CCC #362:
The human person, created in the image of God, is a being at once corporeal and spiritual. The biblical account expresses this reality in symbolic language when it affirms that “then the LORD God formed man of dust from the ground, and breathed into his nostrils the breath of life; and man became a living being.” Man, whole and entire, is therefore willed by God.
CCC #364:
The human body shares in the dignity of “the image of God”: it is a human body precisely because it is animated by a spiritual soul, and it is the whole human person that is intended to become, in the body of Christ, a temple of the Spirit:
Gaudium et Spes 14 § 1:
Man, though made of body and soul, is a unity. Through his very bodily condition he sums up in himself the elements of the material world. Through him they are thus brought to their highest perfection and can raise their voice in praise freely given to the Creator. For this reason man may not despise his bodily life. Rather he is obliged to regard his body as good and to hold it in honor since God has created it and will raise it up on the last day.
CCC #1004:
In expectation of that day, the believer’s body and soul already participate in the dignity of belonging to Christ. This dignity entails the demand that he should treat with respect his own body, but also the body of every other person, especially the suffering:
1 Cor 6:13-15:
The body [is meant] for the Lord, and the Lord for the body. And God raised the Lord and will also raise us up by his power. Do you not know that your bodies are members of Christ? . . . . You are not your own; . . . . So glorify God in your body.
To the thread in general, not necessarily to MTarcisius:
God decided to create an order of beings that consist of a joining of the spiritual and the physical into a single nature. I don’t feel comfortable saying that He shouldn’t have done so, or that part of the joined nature is bad.
I can show God my love more because my body is imperfect. For example, I can kneel in prayer even though I have a bad knee and offer my pain to Christ in reparation for my sins.
I can sing to God with my body, and for me that is a great joy that I don’t experience when I sing only in my mind. My body and soul join together to praise God. (I know it isn’t the same for everyone, but I can only say about me.)
With my body, I can see the glory of God’s creation, smell a flower on a gentle breeze, hear the song of birds, feel the hug of a friend or family member.
Death is only a worthwhile sacrifice for God (meaning martyrdom) because life before death is good. And life before death requires a body.
To the OP:
You will never be absolutely perfect in this life. But there is joy in conquering any temptation to sin. If you start there–for example, “today I was tempted to lust and I controlled myself so that I did not welcome the lustful thought and sent it away” or “today I thought about how good I am at (whatever), but then I remembered that my talents came from God and turned the thought of pride into a thought of gratitude”–you will find it a lot easier to welcome this life that God has given you, and the grace that He sends so you can have those small victories.
Fleeting thoughts that go through your mind are not sins. The sin is in welcoming, accepting, and/or dwelling on the thoughts.
I would recommend that, if there is an Adoration chapel somewhere around you, you should take your pain to Christ in the Eucharist. Don’t just go once and then if it doesn’t “work” give up.

It will take a few times to get there. And keep going to Confession.
Think of it as building something–building yourself. The important thing isn’t to be perfect all at once, but to keep getting better. God knows, much better than you do in fact

, what you can and cannot do. Do your best in this life, and God will see that you become perfect afterward.
I don’t know if what I’ve said helps, but I will pray for you as well.
–Jen