She (F/27) withdraws emotionally during even small moments of tension and I’m (M/29)starting to feel emotionally exhausted

I’m a 29 y/o living in Berlin. My girlfriend and I are both Chilean and honestly on paper we match extremely well. Same humor, similar background, we get along naturally, she’s caring and generous, takes care of me when I’m sick, etc. We’ve been together about 3 months.
The issue is emotional dynamics.

Most of the time things are genuinely great. But whenever there’s even the smallest emotional tension or change of plans, she completely withdraws. Her whole energy changes, body language changes, she goes quiet and emotionally distant. For context, she has diagnosed clinical depression and takes Prozac.

Even situations I wouldn’t consider conflict become emotionally heavy for her.

Example: friends invited us to a lake. She said it didn’t work for her schedule. I immediately said no problem and we could do another plan. No argument, no pressure. But she still became emotionally withdrawn afterward.

Then at the lake she smoked weed (we had smoked together many times before) and spiraled internally. She later told me she became convinced I was judging her body/looks even though I had been complimenting her the whole day.

She disconnected almost completely from me and we barely spoke emotionally for 2 days afterward.
After a long talk, she told me she’s also been emotionally guarded because early on in dating she wanted me to say “I love you” more often, and I told her I prefer saying it naturally and meaningfully.

Apparently that hurt her deeply and she’s carried insecurity from that moment even though I thought we had already resolved it.

She also says she feels she constantly has to “adapt herself” to me because I ask for communication during conflict or emotional tension.

One thing that hit me hard was her telling me that my outlook on life is “too positive” and that I always try to fix problems instead of “letting them be.” I’ve had a difficult life in many ways and I’ve intentionally worked on staying resilient and solution-oriented, so hearing that confused me a lot.

What’s difficult for me is:

I feel like I’m always the emotionally stable one
I’m constantly trying to repair disconnection
she avoids emotionally difficult topics because she says she prefers ignoring problems instead of analyzing them
she tends toward very pessimistic/fatalistic thinking
she needs a lot of reassurance/validation/affection to feel secure, and after a while it starts feeling performative to me instead of natural

The confusing part is that when things are good, they’re genuinely really good. We laugh a lot, have chemistry, similar values/background, and she clearly cares about me.

But emotionally I don’t feel like the relationship is deepening. I feel more emotionally vigilant than relaxed lately, and more like I’m becoming a caretaker/source of validation than an equal romantic partner.

I’ve also previously been in a relationship with someone emotionally unstable, so I’m aware that I may be extra sensitive to withdrawal/disconnection dynamics.
I’m trying to understand how people differentiate between:

a relationship dynamic that simply needs time, communication and emotional adjustment,
vs
a deeper incompatibility in emotional needs and communication styles.

For people who have been in relationships where one partner tends to withdraw/shut down emotionally while the other seeks communication and reassurance through discussion:

what helped you figure out whether the relationship could become emotionally healthier?

what signs showed you the dynamic was sustainable vs emotionally draining long term?

and how do you avoid slipping into a caretaker role while still being supportive of a partner struggling with depression/insecurity?