Unfortunately, in any parent - child relationship there can be a huge mis match between what the parent intended and what the child perceived.
That doesn't diminish your feelings but, for adults that make it to adulthood relatively unscathed, they are able to appreciate the intention of the parent as they mature.
Most parents really do their best in the circumstances that they are dealing with at that time.
This is important as, when you were ill, you won't be aware of what else your mum had on her plate - marital difficulties? (i see you neither blame nor mention your dad) financial difficulties? health worries about her own health/another family member besides you/work worries?
You just won't know unless you can have a conversation.
Of course, none of this takes away from the fact you didn't feel loved. But, if you can understand her reasoning, then it might help you to see that she made what she thought were the right choices at that time.
You say you're now a parent but you don't say you're a parent to teenagers.
The early years of parenting are a breeze compared to parenting teenagers. Often, by the time there is a teen or two in the family, there are younger children also who have needs to be met. Women can be menopausal at this stage and worried about their own parents' health.
So, i'm not saying your Mum is entirely blameless, only that you need to look fully around with your eyes wide open to understand her actions.
Writing her a letter explaining how you feel might encourage her to write back and explain what she was thinking at that time.
And - if you get a response that fuels your emotions, you have something there to take along to a counsellor for discussion.