Hi there,
I am so sorry to hear you are going through what I am sure is a very difficult time. I must say, Jon's post is great and thorough so I am not sure I can do much more except reiterate some of his points with some of my own points to add another perspective.
An interesting thing about mindfulness is that many often find a great deal of peace within it. Because mindfulness gives us more control, in some ways, over our minds and, therefore, how we experience our feelings - or whether we experience them - it can give us the ability to push thoughts (and feelings) away, at least for some time. However, that doesn't mean it is what is best for us (as you seem to be aware of yourself) and it doesn't mean we always know how to use mindfulness to go into our feelings.
BUT mindfulness CAN be used to go into our feelings. Now, I will warn, that doesn't mean it is a pleasant experience. In fact, you really do want to practice mindful emotion work with a great deal of self-compassion and gentleness. So, I tend to use a combination of techniques and I am going to include links to some free, guided meditations I have for each technique if you want to try them and need the support (but feel free to use other resources or search for other resources as there is lots out there and mine if just the options I know of off-hand).
When dealing with painful or difficult emotions:
A) I start with a lot of self-compassion work, as Jon points out too. So I might start with a few sits where I use a meta meditation for myself. So a meditation like this (
https://youtu.be/EBrnHl7gp-o), but ALL directed to myself, don't worry about others for now.
B) I would then do some self-compassionate problem solving work to sort out what I am really feeling, what I really want, what the real feelings/challenges are (
https://youtu.be/jCpAxnEJuJY).
C) When I come up against really big & difficult feelings, I would use a meditation such as this (
https://youtu.be/hPgdHlSXkd4) to help you be able to just be with them instead or trying to avoid or numb them (if that is what is happening)
D) If there are challenges I notice in particular I might use a mix of meditations specific to those need such as ones that focus on forgiveness (
https://youtu.be/RWi0BnO0QvU), or impermanence (
https://youtu.be/p4q0f0AhFNs), or even expansion to help keep things in perspective (
https://youtu.be/ELvTzR8YUhk)
E) I then use positive outcome visualizations or meditations that allow me to immerse myself in the possibilities of what might be next to help give me the courage to face any difficult actions I might need to take or to visualize who I want to be in various scenarios to deal with the issues.
F) I would cycle back through any set of meditations needed to keep sorting through my feelings as required.
Otherwise, I would also use a journal to help support these processes as sometimes journalling what you noticed, what surprised you, what you take away, and what you leave behind out of a meditation can help with processing. And, keep that love and kindness meditation in mind for yourself - you DO deserve to feel loved and supported and please know that your feelings and wants matter. They matter a lot, but we all have to be our own caretakers for what we want, so allow yourself to be your own friend through this - being gentle and loving but doing what you feel is best for you along the way. As Jon says, just because meditation helps us feel less affected by our feelings and thoughts, doesn't mean we have to let go of them. Being forgiving and non-judgemental, doesn't mean giving in. In fact, being truly authentic and fully loving and compassionate means quite the opposite.
And, remember, sometimes even the strongest meditators need other's help. I don't know exactly how you're feeling or what might come up if you go into your feelings more deeply but please, please don't shy away from therapy or coaching or friends' support or whatever help you might need as it arises. I know there have been times where I felt like I should be able to fix all my own stuff because I am a meditator and have been in the practice for some time, but we all need help sometimes - even the most experienced meditators, and there were some things I wouldn't have been able to get over (or get past as effectively) without some coaching or therapy to supplement my practice and even work WITH it. So I mention it as a "just in case" because it IS important and I feel like people need to know they aren't the only ones who needed help or feel the way they do.
Feel free to message me if you have any questions or need further support. It's a great community here and I am glad you reached out.