Everyone keeps a small private list of feelings they believe disqualify them: the flash of envy at a friend's good news; the relief threaded through the grief; dreading the trip you also genuinely want to take; the sudden strange thought that arrives from nowhere and means nothing. The list feels shameful precisely because it is kept private - each of us assuming we are the only member of a club that, in truth, contains everyone.
The facts are friendlier than the shame. Minds produce odd, dark, contradictory material as routinely as they produce dreams - it is standard equipment, not a defect, and the strangest passing thought says as much about your character as a cloud says about the sky it crosses. Mixed feelings are not a moral failure; they are what feelings are like when the thing you love is also the thing that exhausts you. None of this is on the list of what's wrong with you. Most of it is on the list of what a person is.
So write the thing down - the exact feeling, without first sanding it into something presentable - and then write it a second time as a member of the species: a person whose friend succeeded felt envy beside the joy. A tired host counted the days until the visit ended, and loved his guests. Written that way, in the species' ledger instead of your private file of evidence, the same sentence weighs a fraction of what it weighed an hour ago.
What acceptance buys is not resignation - it is handling room. A feeling treated as an emergency about your character must be fought, hidden, and monitored; a feeling treated as weather can be felt, written, and let pass. You'll find the second kind passes sooner. It always did; the fighting was what kept it.