How can one deal with the problem of urine drops exiting after urination, which leads to feeling that clothes are ritually impure and abandoning prayer, especially with the difficulty of constantly changing and washing clothes?

Abandoning prayer is a grave sin, and you must repent and be diligent in performing it. As for drops of urine: if it reaches the level of incontinence (meaning you don't find enough time to pray with proper purification), then perform ablution for each prayer after its time has begun and pray. If it does not reach the level of incontinence (meaning you find time for purification), then be careful and wait for that time to perform ablution and pray. If you doubt that impurity has reached your clothes, then base your judgment on the original state, which is purity, until you are certain. The Malikis are lenient regarding external impurities, so they do not obligate their removal.