Thanks for your questions. I wondered when someone would write about this. You are the first! Remember that I described two distinct and sometimes-confused (with one another by dioceses) ways of living eremitical life: 1) as a solitary hermit who may, but need not join with other already-professed solitary hermits in a laura or colony, and 2) in a semi-eremitical community of such hermits under a single Rule where one is professed as part of the community. In the first situation, under c 603, each hermit must take care of her own finances, insurance, medical care, securing of spiritual direction, housing, formation, ministry, etc. Such hermits can come together (c 603 does not prohibit this) in a laura (colony) for mutual support in the solitary eremitical life. What must remain true, however, at all times, is that the individual hermit be able to live her own vocation according to her own Rule of Life, her own horarium, and so forth. S/he is not part of a juridical community per se and is not (and cannot be) required to be a caregiver in an ongoing way to another hermit in the laura.
This does not mean such a hermit will not assist other hermits in the laura at all!! But her vocation is a fulltime reality and she was professed to live that with fidelity. If she has a relationship with a parish community, has a ministry (spiritual direction, writing, retreat work, and so forth) she must be able to carry this out as she discerns she is called to do. If she can accommodate the needs of another hermit (especially if a more fulltime or ongoing caregiver is also secured by the one in need), then she should certainly do that and to whatever extent is reasonable, but she simply cannot be required to be a fulltime caregiver to a c 603 hermit who must provide or have provided for this as part of her own profession under canon 603. In a laura, there should not be a problem with a caregiver coming in to provide what is needed for a single member. If this is not possible then it may be necessary for the hermit in need to spend some time in a care facility until she can return to the laura and care for herself or receive in-hermitage care from someone coming in to do this.
Let me be clear. I am not speaking of someone who has the flu, needs assistance once or twice a week for something, or who breaks her arm and needs someone to come in to prepare or help her prepare a meal each day, get a shower, or do her laundry for her, for instance. Neither am I speaking of a hermit needing a ride to the doctor's occasionally, as we all do, which another hermit can easily provide with enough planning time, etc. Nor am I speaking of an emergency when all kinds of plans go out the window. I am not even speaking of a situation in which a c 603 hermit discerns she can give a month or two to the ongoing care of another without a significant threat to either person's vocation. I can easily envision all of these being possible and necessary. I am speaking of ongoing long term significant caregiving which would disrupt not only the ill person's own horarium and perhaps her ministry, but that of others in the laura as well. For everyday illnesses and accidents, and also some temporary rehab situations, for instance, I definitely would expect c 603 hermits to be flexible and generous enough to assist one another with these! But this needs to be discerned by each member of the laura. For the rest, if a hermit needs a caregiver, she should secure one or several who can trade off (this could work well in terms of the local parish if members know the hermit's needs, for instance).
The situation in a semi-eremitical community of hermits under a single Rule, etc. differs significantly because the community itself is a central, not an incidental part of the hermits' vocation (in fact, it is significant here that I write hermits' vocation, not hermits' vocations). A hermit in such a community will have vows which include and are made in terms of the communal dimensions of her commitment. Religious poverty is geared to living poverty in community, as, in such a situation, is religious obedience. Meanwhile, chastity is a form of loving defined not merely in terms of loving others chastely generally, but of loving one's brothers or sisters who are similarly committed in this institute. There will be a common mission statement, a common charism, and a common spirituality in which each member will have been formed. The community is family -- it is a single juridical reality -- and is canonically constituted as such; it is not merely formed for mutual support by those already and otherwise committed to a c 603 vocation who are thus canonically obligated to continue living it should the laura fail, dissolve, or be suppressed.
In all of these cases discernment and true generosity is needed, but the two situations are vastly different from one another because the hermits' canonical (public and legal) commitments are different. This may point not only to the reasons true lauras fail so often, but also another reason some dioceses allow or even encourage lauras to morph into true juridical communities. It is sometimes seen as onerous for a bishop to be responsible for several hermits in his diocese (I know of one diocese, for instance, whose relatively new bishop refuses to meet with individual c 603 hermits but instead requires they come together as a group if they require his input; this is not what canon 603 envisioned or requires). Others may refuse to profess c 603 hermits unless they belong to the laura and are formed in this context. But canon 603 was designed for solitary hermits and was meant to preserve, nurture, and govern a rare and meaningful vocation which a given diocese might, in fact, only see a single instance of over a period of decades. While each c 603 hermit might well enjoy and appreciate the opportunity to live with others similarly constituted -- or to come together in such a way for some time each year or month -- and while each c 603 hermit lives a strong ecclesial dimension in our vocations, we remain solitary hermits who must live as such every day of our lives unless and until we discern a different vocation.