Are the repeated impediments to becoming engaged to a girl and the hesitation in confessing to her an indication that there is no good in this engagement, or are envy and the interference of others the cause? And could this delay harm his reputation or her relationship with him?

Your shyness might be the reason preventing you from proposing directly to the girl. The remedy for this is to propose to her through one of your relatives. You must stop meeting and speaking with her until you have performed the legal marriage contract with her, along with repenting to Allah Almighty for what has passed, as it is not permissible to have a relationship with a non-mahram woman outside the bounds of marriage. Our advice to you is to hasten to propose to the girl if she is a woman of religious commitment and good character, for the best remedy for those who love each other is marriage.