I am deserving of a long-lasting, fulfilling relationship

Deserving sounds like a verdict someone else hands down, as if a panel somewhere is reviewing your record: the relationship you stayed in two years too long, the one you ended badly, the year you were hard to be around.

No such panel exists. What exists is a long relationship built out of ordinary materials, patience, honesty, a willingness to repair, and none of those materials check your history before they work.

You don't clear your past and then qualify. You practise the things that make love last, starting today, with whoever is actually in front of you.