Learn how transference work and work backwards. Like you have this killer feeling about something or someone and let us say this feeling is global meaning you feel it often at different degrees or at different people. You stop and ask why? Keep asking until you get to the bottom of your source/core/tension.

People go to therapy to get attached and then get unattached. Does this remind you of something? Yes a parent and the baby.
Too much attachment and then detachment in healthy way without humiliation and shame but probably some hurt and disappoint. And boom you are gone to your world alone or with with someone but not with the therapist.

So in essence, you can teach yourself how to detach from your past without that intermediary of therapist by becoming conscious of your feelings such as extreme love like obsession, extreme anger, or hate or control or envy...anything that requires much energy and you work it with your background...how did you get that.

Self-therapy, you need strong motivation to change, time, and effort of documenting your progress somewhat.

simple.